Charge Lithium Batteries correctly (LiFePO4)

[@langstonholland9272]

This may be the single best overview of LiFePO4 battery charging available. I have also purchased the BankManager and tested it on my bench and it works as advertised. I've done my best to confuse it or break it and failed on both counts. Highly recommended.

[@SVAdAstra]

I'm an engineer: NASA retired. I listened very closely and critically looking for any errors. I found none. Well done!

[@AZRockRunner]

good landing gears, well done :)

[@deefer66]

really.. NAS engineer who agrees you can go past 100% charge?

[@Clarks-Adventure]

@deefer66 Neither he nor I said that. Watch again. The point is you must stop at 100 percent and that is difficult to do in an actively used syatem

[@joeblaney684]

Clark big fan but even I struggle with a 40 minute phd in Lion charging

[@deefer66]

@@Clarks-Adventure No he did.. 12:12.. it'll go to 100% then hockey stick...

[@FutureSystem738]

Great description thanks. I have worked with LFP batteries for a long time- and can’t find any fault with your analysis. 👍

[@mikeg7924]

Great presentation Clark. I just got an email from Redodo announcing that they have created a 140ah dual purpose battery with ~900 CCA that can start engines. Sounds like a great idea for your next video. Thanks for the great videos.

[@Clarks-Adventure]

LiTime has a battery with the same specs coming out. Bet it's the same. I have one being shipped to me for review

[@donlindell1994]

Am I the only one who hears Clark’s voice in his head when you read the Bank Manager’s manual? It’s well written but I felt like Clark was sitting in bed next to me reading out loud the whole time I was studying. You’re lucky the dog didn’t wake up and bite you!

[@PazLeBon]

bit g ay mate tbh

[@Boosted-Logic]

I, too, read several whitepapers and immediately realized that I needed a better charging system for my lithium - - especially after a low cost charger ruined my e-bike batteries. Having recently purchased / built a Riden bench power supply I realized that the latest firmware update ;provides a very sophisticated algorithm that starts with low voltage constant current (amperage that you specify) and then intelligently switches to constant voltage to the max voltage that you specify. After datalogging the volt & amp curves over time I'm very pleased with how well it follows best practices. Not sure the Riden makes sense as a charger for a marine environment as it is max capable of 60v/16A max and - - more critically - - requires manual intervention to instantiate charging. Perhaps interesting to incorporate their algorithm into a marine system somehow? Thanks for the video Clark. Timely and informative as always.

[@Clarks-Adventure]

Actually that is just constant voltage with current control. Pretty easily found out there in any balance power supply. But it's exactly what you need as long as you have a way to shut it down when necessary. I'm glad you are treating your cells well. This works for you because your battery is either on the bike working OR on your charger. In an active off-grid system we have loads coming on and off while charging and with solar we can't control the charger output current. That makes the solution a tad bit more complicated.

[@Boosted-Logic]

​ @Clarks-Adventure The Riden has auto-cutoff once the target charge voltage is achieved. So seems ideally suited compared to the low quality / garbage e-bike chargers that cost nearly as much as the Riden kit. Good points re: the complications with off-grid charging. I wonder... could current dumping via heat gun or similar be a way to (somewhat) manage charge amperage? Would be very interested to see a video of how you stage 3 battery banks with separate bank managers. Seems clever but please more details. 🙂 Thanks again. As always, very informative. - John in Switzerland

[@Clarks-Adventure]

Yes. With that feature and the right voltage selected for the size battery being charged this would be perfect for charging a battery disconnected from any load

[@Trackhoe075]

Listening to all this just confirms why I love my whole house ng generator i literally never worry about having power to do what I need to NEVER! Let me repeat NEVER! I always have charged batteries if I need them for tools and the like! Having a 110 plug in my car is total nonsense especially with only 150 watt capacity If I needed that cause I was in the car and needed to charge batteries for tools I’d find a 12v adapter ( they do exist) and charge them enroute or before I left The worse case scenario I always can fire up my 10k generator that’s in my pickup bed I’m just old school and it’s worked just fine for me these 60 plus yrs But you guys do you and I’ll do me if it works don’t fix it is my motto Have a nice day Enjoyed the vid regardless

[@rcinfla9017]

Biggest consumer screw up with 12v self-contained LFP battery is not fully charging often enough to balance the SoC on the four series connected cells. The more the cells get out of SoC balance the lower the available capacity of battery and the greater the likelihood the BMS will prematurely shut down charging due to a single cell reaching full charge before other cells causing it to exceed 3.7vdc maximum allowed cell voltage. Most BMS's do not do any balancing until a cell gets above 3.4v. You should fully charge to at least 4x 3.5v = 14.0v and hold the 14v for one or two hours to give some time for BMS to do cell balancing. One or two hours held at 14.0v is not a damaging overcharge for LFP four cell battery. If you do not fully charge LFP for many months, it can get so out of balance it will take many hours held at 14.0v to get battery cells back in balance. For a 100 AH battery, 1% cell SoC imbalance will cause premature BMS charging shut down when attempting a full charge due to an overvoltage cell. Most internal BMS's in 100 AH LFP battery only have a balance bleed current of about 50 mA. To balancing out 1% of 100 AH battery, 1 AH, with 50 mA balance bleed will take 1.0 AH / 0.05 A = 20 hours held at 14 vdc. You want to avoid getting into this situation by keeping up with cell balancing by fully charging at least every couple of months.

[@josephamaral419]

THIS, I have no idea how people keep thinking they know more than the engineers who designed these batts and fail to read the literature on tests done on the cells. They are designed to go to 100% and to 0% over and over again, with minimal degradation. Calendar aging will be worse than any degradation you can do in a system that does low c rates. I wish everyone followed the instructions you just mentioned and your comment is very underrated. People who are babying their batteries hard will die first with their batteries still having lots of cycle life in them, basically a waste. Use your battery's energy before they age because you will never get that capacity ever again in the future.

[@Vindsong]

I have abused a gen 1. BankManager with the software upgrade for two years now and I ABSOLUTELY LOVE IT! Buy, install, forget. It is literally how it has worked for me. I LOVE IT!!

[@andrievbastichy8551]

love the intro... i actually shouted "ahoy!" at my screen.. and funny enough i just randomly clicked this video.

[@SalingSamantas]

Nice Clark! I love listening to these. The deep dive the deep technical stuff. You say you retired from engineering but I think you're still doing a little bit of it. Thank you for doubting it down for us regular folks. That means a lot!

[@lonnieschreiner5879]

Thanks for the great information. Just purchased a used van conversion with lithium batteries so trying to learn all I can.

[@Clarks-Adventure]

You are very welcome. And congratulations

[@brownnoise357]

Great Discussion Clark 👍 I do like AGM Batteries still, as I know for long Service Life, they need to be kept at a minimum State of Charge of 80 % - just adjust the Bank Size accordingly, which means with say an 800 ah bank, the Maximum you can use overnight before Solar kicks in again, is 160 amps from them which Flatlines the RechargeCyclesso they never reduce- which on a Sailbat, for me, is plenty. Then Bank 2 is Lithium Lifepo4 - likely 4 x 230 ah Plus type Batteries, in an overall management role of looking after the AGM Bank, plus engine Start, Generator Start, Windlass and Bowthruster Batteries. so 900 ah, but so the Recharge Cycles for those never fall - according to Ampere Time, which became Li Time - you never let the state of Charge drop below 50 % which means at least 400 amps is available to keep all the other Batteries on the Boat Happy . If sailing between places, then a pretty decent engine alternator, or the Generator, if it is cloudy or Raining, then the Bank Manager will assist in the Lifepo4 Bank Role, by looking after that Bank, by making sure it is looked after properly First, so from the Lifepo4 Bank, DC to DC Chargers look after every other Battery, or mix and match with other Battery managers as well - how best to low stress divide the Workload , is doing my head in at the moment. Top Solution for managing Lifepo4 Batteries is your Bank Manager right now Clark, but the new lightweight Victron DC to DC Chargers may be up to handling AGM Batteries ok for keeping them happy ? 😅 Sorry Clark, I'm not exactly with it right now, a Nurse put compression Socks on both feet, but the one on my Left Foot caused the Skin on my foot to fall off, and the pain killers are driving me a bit DooLally, but at least they are working, and so far so good - No infection. Best Wishes, and Keep Up The Great Work. Bob in Wales. 🤔🌟🌟🌟👍😄

[@Clarks-Adventure]

I hope you recover quickly

[@brownnoise357]

@@Clarks-Adventure Thanks Clark. leaving the Circulation Socks off, a course of Antibiotics, and Cocodamol Painkillers seem to be getting on top of things Fast. Not usually a fan of dodgy Paracetomol, but 1 tablet 12 hours apart seems OK, I've avoided having Antibiotics for nearly 50 years, and now I need them, they are working, so things look up. All the Best, and Fair Winds Buddy. Bob. 🤔🌟🌟🌟👍

[@elmer665544]

Good video and very nice work on the bank manager. That said, the Victron systems are very good! I have designed, built and used 3 different systems over the last 6 years and have a BS in electronic engineering. The Victron systems can also get you a long and healthy battery life if programmed correctly. I use 13.8v for reset and 13.9v for charge voltage. For my Epoch batteries it puts you right at the level that the battery cells begin balancing if out of balance. The current gradually tapers at 13.9v and the programmed delay time and tail current settings establish the 100% reset. It is very accurate with 99% efficiency setting and 1.01 for Peukert exponent.

[@Clarks-Adventure]

Hi Elmer, I like Victron stuff as well. In fact I have a box of blue boxes waiting for me on Temptress. I'm glad you have a working system you like. But, what would happen if you charged at a higher C rate? Or much lower? I stand behind what I've said in this video for the perfect charge. But as long as your batteries last long enough for you, that's fine right.

[@elmer665544]

Both high c rate and low c rate charging naturally taper current at 13.9v in the constant voltage phase as you hold voltage at the knee of the charge curve. I expect my batteries will diminish due to age before they diminish due to high voltage dendritic formation.

[@Clarks-Adventure]

Try this. Discharge a battery to 20 percent. Then charge it at .5C. It will go right past 13.9 and accept that current. The correct terminal voltage for .5C (when the cells are full) is 14.6v. I bet the voltage will hit 13.9 at like 60 percent full

[@elmer665544]

@@Clarks-Adventure I have the utmost respect for your bank manager and the process you use. It is probably technically better than the Victron component charging scheme that many manufacturers also use. It is very good so don’t misinterpret my comments. I am just defending that the Victron charging scheme is actually also very good in practice. I can’t hit the.5c charge rate as I have a 900+ amp hour bank so I have no actual data on that however I can observe the system behavior and have many many many days under a variety of conditions. At a set point of 13.9v the bank will accept maximum current then the current will gradually diminish towards zero. As the tail current goes under the 2% tail current the batteries are at about 99% if the charge efficiency is set to 99% and the Peukert exponent is set at 1.01. I am getting little drift so far.

[@SailWhiskeyDream]

I need to replace batteries in the next year or so, This is helpful.

[@tubeuser2350]

Nice video, with the information very well presented (as usual). If I may add on a bit, the "Charge to 80%" thing for electric vehicles is specifically because of the use of NMC (and related) Lithium battery chemistries that really don't like to sit at full charge. They also don't like sitting at low SoC either. "Keep them between 20% and 80%" is the rule for maximum life in most EVs. My own EV is from 2010, and the original LCO-based battery still has 80% of its capacity after nearly 15 years / 62,000 miles on the road; that rule is ingrained in the car's battery management strategy, and it appears to have worked. The LiFePO4 chemistry doesn't suffer from this, so if you buy a car with LiFePO4-based battery cells you can charge them all the way up and drain them down pretty far on a daily basis without worrying about damage. That can substantially make up for the lower energy density of the LiFePO4 cells in the EV environment. So what that means for LiFePO4 batteries in RVs and boats is that we don't need to worry quite so much about battery stress due to high SoC. It's still very important not to overcharge them, as you point out, but bringing them up to a proper 100% and leaving them there should be fine.

[@uhjyuff2095]

Check out the Engineering Explained video on EV battery charging its a great video and talks about the different lithium battery chemistries.

[@Clarks-Adventure]

Yep, there is a link to it in the description of this video

[@davesmith2150]

I ruined lipo4 home solar cells going past 80% and below 20.

[@projecttrawler]

Such a wealth of knowledge, thank you sir!

[@EngineerMikeF]

Thanks for the subject matter coverage. What would be really helpful in the description are a) short bullet points stating the principles indexed by b) the minute marks in the video where you discuss each point

[@SkypowerwithKarl]

Of course you charge to a voltage for LifePo4. Absolute Max is 3.65 volts per cell. For maximum life the 3.45 volts per cell(if the battery’s balance function works that low) the difference in capacity between these two voltages is negligible. The lowest you can take a cell is 2.5 volt per cell but most people stop at 3 volts. A good BMS (battery management system) won’t allow the battery outside of these ranges. There are only two points where capacity on a lithium battery is true, full and empty voltage with little to no load. Anything in between is a rough guess and only a coulomb meter is accurate and that is initially set at the full voltage. A good charge control will not abuse the battery and keep the BMS from stepping in(the last line of defense). The charge control will have settings like bulk or absorb (3.45 volts per cell) tail current, the amount of power as it reaches full or bulk and absorb time. The better your cells are balanced and the better quality of the BMS’s balancer(active type) the less time is required at the higher voltage. The less time at the higher voltage the better. There may be a setting called float. Lithiums don’t really need float, so I disable it or set it to 3.35 or less. All voltages I gave are per cell. A 12 volt has 4 cells, 24V has 8, a 48V has 16. Heat is indeed a killer of lithium so under hood temperatures should be reserved for lead acid batteries. Always use the recommended voltage printed on the battery if you can’t change the settings like balance start voltage via Bluetooth (3.4 Volts per cell). Lastly if you need a 48 volt battery, buy a 48 volt battery. Do not put 12 volt batteries in series because they will become unbalanced. There are too many variables to be answered here so ask questions on forums like DIYSolar

[@Clarks-Adventure]

You do that. They are your batteries

[@SkypowerwithKarl]

@@Clarks-Adventure And very happily for a very long time.

[@SkypowerwithKarl]

Yeah, I can get behind what you said. Pretty much the first time I’ve heard that about float voltage and wear. I’ve just been setting all of them to 3.35 just so it’s not hanging around in higher voltage after absorb, yet still retaining available capacity. Many systems don’t have an absorb time setting option but an algorithm that’s set by battery chemistry selection. Sometimes I find the absorption time too short (non communication batteries) in this case so I’ve found the BMS’s with an active balancer to be a game changer when time is limited at absorb. You can go weeks without full charge without worrying about delta differences.

[@SkypowerwithKarl]

@@junkerzn7312 I love Victron for those reasons and they are superior for boat, RV and some off grid applications. Unfortunately they don’t meet approval in some residential locations or too modular, not enough kw. They are so dang users friendly.

[@Clarks-Adventure]

@junkerzn7312 how does one charge to a constant current in a live system and using solar?. Both loads switching on and off and the available power change the C rate.

[@kishanmajethia]

Memory effect in lfp works differently. What you explained is different kind of memory effect observed in other cells

[@tomhenry4993]

Lookin' good, Clark! Keep it coming...

[@Clarks-Adventure]

Thanks Tom

[@johnnylightning1491]

Clark, what is a good way to discharge a lithium battery if it's not connected to your system and it needs to go into storage? I have this situation. Good video and you'll get several watches from me because I need to understand this stuff. Keep the good stuff coming.

[@Clarks-Adventure]

Any load. Whatever pulls out power. Just track the amps and hours do you know when to stop.

[@evanmayer744]

A simple resistor! Or if you don't have one - an incandescent light bulb. Perhaps a DC motor, like a PC fan?

[@TheCornucopiaProject-bd5jk]

One reason why charge controllers may ask for charging voltage is older LI batteries had a variety of different chemistries and configurations. So the charger is asking what the manufacturer specified. Most batteries are LFP now and bms have evolved, so they pretty much all operate at the same voltages. But both older chargers and batteries are still out there. Setting battery state of charge to 20/80 destroys the advantage LFP has over Lead acid. BMS’s vary, top brand batteries usually also use top end BMS, while budget brands may skimp a bit. Although some budget brands like Redodo and LITime are giving them a run for the money, It comes down to what BMS features you want and shop around based on that. With warranties for 3-10 years and charge cycle guarantees of 3500+ cycles it’s hardly necessary to limit charge and discharge ranges. Some confusion comes from older information from different chemistries as well as similar number confusion. (DOD 80% vs 80% capacity after 3500 cycles). IF, just IF you happen to have or need multiple housebanks, than a bank manager can be useful. For pretty much anyone else, it’s overkill. Your LFP batteries will last 10+ years with full daily cycling. Yes they will end up with only 80% capacity by that time, but that a small price to pay. The only reason a 20/80 charge/discharge limitation is good, is because it artificially limits your usage/capacity. If a charge cycle is 100amp, I can’t discharge below 20% and only charge up to 80%, that leaves my usable energy at 60% or 60ah. It would take 2 days to account for a full charge cycle and thereby giving the illusion of a longer life span. You’d also need twice as much capacity to cover your needs, which is what we do with lead acid batteries. My recommendation is to use the full range of your batteries capacity. If balancing is important to you, get a battery with active balancing build in. Otherwise, you can manually balance the batteries (disconnect and charge individually) once a year. Battery technology is advancing fast these days. Chances are you’ll replace your batteries after 10 years just to be more up to date. Old batteries can still power a garage or other things.

[@TheCornucopiaProject-bd5jk]

One word on charge controllers. It’s not the job of the charge controller to balance battery cells. It’s the bms job. Some brands like victron also sell batteries. To optimize their system they allow the charge controller to directly communicate with each battery. Larger home system using server rack batteries do this as well. The small battery market for the most part has not yet incorporated direct communication. Give it two more years and it’s probably a standard feature.

[@benkanobe7500]

Thank you. Excellent. I am still going to watch it a second time because my system is strange: No solar (for charging batteries). Daytime production is high enough to run an 120VAC charger powered by inverter to recharge LiFePO4 and AGM mix.

[@fratermus5502]

> Charging to a voltage damages Li period The oldest instrument LFP bank I know of (Rod /Maine Sail's bank assembled in 2009) begs to differ. Charged to 3.45Vpc for thousands of cycles and still meets rated capacity.

[@Clarks-Adventure]

That can happen as I described. There is of course a proper voltage given all the other variables. But in an active solar charged system that's not really possible

[@haydenwatson7987]

On my two Victron IP22 chargers they are easy to program to charge in absorption mode based on tail current. It is not in the base programs but not a problem by going into the advanced settings - expert mode. I think the same is true of most Victron chargers.

[@Clarks-Adventure]

Great for lead. If I was you I'd use it. But for it to work the charger would have to know the current actually going into the battery. For a Victron I guess that would mean a smartshunt on the negative terminal of the lead bank. It's, of course, no help for Li.

[@olafschermann1592]

At least Victron chargers have the states: charge - absorb - float 90% of all chargers stop at a voltage and stay at absorbtion state without droping to float. Victron works with a timer - not as perfect as your soltution but better than everything other.

[@Clarks-Adventure]

Yes, That is fine for lead

[@haydenwatson7987]

@@Clarks-Adventure It does know what is actually going into the battery. The IP22's have synchronized charging that communicates with the Smart shunt to base the tail current on the amps going into the battery. I have tested it and once it drops to my chosen float at 13.3v it will not go back up even if I turn on all of my dc loads and take the charger output up to +20A.

[@haydenwatson7987]

@@olafschermann1592 If you go into the advanced options, "expert mode" you can charge to a tail current.

[@kenmix6974]

Loved the video. Lots of good information. I would like to see a video about how to set up multiple bank managers, I have 300ah of Battle Born that are about 4 years old. I would like to add 600ah more of a different brand. I currently have Victron chargers for solar, alternator, shore power and wind.

[@Clarks-Adventure]

Someday. Maybe when I get back to the boat. For now it's just like setting up one the second BankManager's contactor's lead side goes to the same lead the first

[@PatricksDIY]

25:17 there are, aside from specific external parts you can purchase separately to include a BMS, or balance board etc. I build my own batteries from fresh cells. Most hobby chargers will charge that way (at least if you are using 12 to 24 volts), I have as ISDT Q8 max, that has balance connection along with "main" power connection, and it ensures each cell is balanced the same so you get the most out of your battery as a whole. It dynamically adjust the charging based on the cells like you stated.

[@Clarks-Adventure]

I looked up this charger. No it doesn't charge the way I describe in this video. You may want to watch again.

[@jaminoes_]

I like Clark's LiFePo4 videos. A lot. But they always end up as a Bank Manager sales pitch.... puts me off a little.

[@Clarks-Adventure]

Sorry. But it is the only thing that goes what needs to be done. And of course I need to advertise somehow or no one will know about them.

[@LeeSurber]

There are indeed charge controllers for LiFePO4 batteries..!! I have been using them for years in my home solar/wind system..!! My controllers handle up to 96v and are fully programmable..!! I run 48v..!! My bank is held at 3.36v/cell,,, just above nominal,,, and are basically acting like capacitors..!! Of course, my balancing takes place in this voltage range as well..!! I do this manually but there are BMS's with programmable balancing voltage thresholds..!! My system is not designed for off grid but will provide up to 4 hrs of capacity (with automatic load shedding) in the event of power failure..!! I use home assistant for everything, even as a BMS, controlling solid state relays for battery disconnection..!!

[@Clarks-Adventure]

Yep. That will kill your batteries nicely.

[@LeeSurber]

@@Clarks-Adventure 4 years so far with 6mv per cell deviation..!! I'm satisfied with performance so far..!! Lots of storms and power outages in Texas..!! System has been pretty well tested..!! Pulling rather large loads with multiple AC's cycling in summer and multiple heaters in winter very consistently..!! No problems at all..!! Batteries are 1.8kw 3C continuous discharge rated so they pull the dynamic loads well..!! They still capacity test just fine..!!

[@bobuncle8704]

Best explanation ever. 👍👍

[@departingthefix123]

Hi Clark, thanks for the interesting video, unable to locate your suggested active cell balancer video which was to follow Regards.

[@Clarks-Adventure]

I did a video on the cell balancer. kzbin.info/www/bejne/Y2bHo6RjqbZjqMk There is a link in the description. Unless you mean the battery balancer for joining a series of 12v batteries

[@departingthefix123]

Hi Clark, thank you for the fast reply, I did manage to find the link you sent about 5 mins before receiving your reply. My bad but thanks again Dave.

[@michaelfitzpatrick3641]

Some useful information on charging LiFePO4 batteries. However in the real world not everyone has your magic Bank Manager and has to do the best they can with existing equipment. New batteries are most always delivered with unbalanced cells. If charged at voltages below the balance start voltage, things will get worse, the capacity reduces and the 'weak ' cell gets a hard time thus degrading faster. Typically BMS balance starts at 3.4 to 3.45 per cell, say above 13.6 to 13.8 volts for a 12v battery. Due to the low passive balance current most batteries use, it can take some time, many hours with the voltage above 13.8 volts, for the cells to balance. With new batteries I recomend using a charge voltage of 14.2 volts, absorbtion period 2 hours, float voltage 13.4 volts. Unless you have Bluetooth or other data access to the cell voltages, that reports cell balance, keep this charge set up for two weeks, ( assuming daily charge cycle). After this period or if cells are reporting good balance at absorbtion volts, a delta of 30 mv maximum, revert to a less agressive charge setting. A useful low stress charge setting is absorbtion 13.8 to 14.0 volts, absorbtion period 15 minutes , float 13.4 volts. A factor often overlooked is calibration errors in chargers and volt drops between chargers and battery. Victron chargers can have actual battery temperature and voltage reported over the built in VE buss by the Smart shunt of BMV712 monitor. This elinimates volt drops and allows chargers to stop charging below pre set temperatures. Where new lithium batteries added in parallel, provided the existing batteries show normal operation and have not been abused, there will be no issues. Normal charge profiles can be used. Any ageing in the older batteries may result in slightly unequal current sharing. The major 'killers' of lithium batteries are high temperature and holding the fully charged battery for long periods at voltages above its full resting volts, 13.4 for a 12v battery.

[@Clarks-Adventure]

I agree with most of what you say. In fact I say it in this video. You do know anyone can buy a BankManager. Just like anyone can buy lithium batteries. You make it sound like the device is unobtainable. It's here: www.emilyandclarksadventure.com/bbms

[@AZRockRunner]

I have top-balanced my cells before I assembled (took weeks). A year later some went out of balanced. But only when the battery is fully charged, and only took 4Ah discharged to bring then back to balanced again. I don't bother to rebalanced them again. I have two banks, 460Ah each.

[@Clarks-Adventure]

I think often this is the case. Especially if you don't over charge. But some batteries have a bad cell that needs to be balanced more often. So I like others have to give rule of thumb recommendations. The balance process is tough in the cells but running a battery when badly out of balance could be worse. So occasional balancing is probably the best advice. But for guys like you. I'd say... Do what your cells need

[@aaronsmith593]

If you charge only to 13.5 volts, then resting voltage rests even lower ? If you charge to 13.48 volts DC on a 12v Lifepo4 battery, you are not getting full charge and balance the cells. All Lifepo4 batteries come with a BMS battery management system that prevents overcharging. Lifepo4 battery chargers usually charge to 14.6 volts DC to fully charge and balance. Then at rest they settle around 13.4 v to 13.6 v. Although I do wish all Lifepo4 battery chargers came with adjustable charge voltages.

[@Clarks-Adventure]

They do. But that's my point, they shouldn't.

[@wendellhammond7853]

Another good one.

[@MyLifeThai371]

Good choice on the title of your channel!

[@Clarks-Adventure]

Thanks

[@AndrewBristol]

Hi, I've been using 3 x 90Ah lead acid batteries (Varta/Johnson Controls) they are all linked together using (in parallel) with 120A cables, I have used the three batteries like this in our camper/caravan. They have been removed during winter months and maintained by a 24/7 fit and leave maintenance charger, during the months of use in our caravan they are maintained by 280W of Solar panels fitted to the roof of our caravan, in between the panels and the batteries I have a good MPPT Solar Controller which I have set to 300w Battery capacity, I have been using them like this for 5yrs and TBH they are just starting to show signs of being tired... Listening to your comprehensive description of how to charge Lead Acid batteries should I have them set to the closeset capacity (which would be 100Ah) ?? I will probably swap them out at the beginning of next season. Obviously I will have to use the Solar Panels on my camper to keep them charged... This leads me on to some questions about charging Li Batteries... Can I use my existing solar controller as the batteries I intend to buy all have internal BMS onboard, I would obviously use the nearest setting on the solar controller to give output of 14.6V... OR should I just throw my old Solar Controller out and fit a Li compatible controller. ie Victron or similar... a 30A controller should suffice with what I'm using on the roof of my caravan. Thanks for any advice you can give.

[@Clarks-Adventure]

For Li you really want a BankManager to do it right. And with a BankManager you can use all your current chargers. For the lead it's not what it's set for that matters, it's the algorithm the charge controller follows that matters. But it's not as vital for lead If you go hybrid with a BankManager the BankManager will "maintain" your lead batteries like your winter device does during every night.

[@jeffoneill3429]

LiFePO4 will develop a memory? Never heard this before. Source?

[@Clarks-Adventure]

I can't pay my fingers in a source at the moment but my friend Conrad (from my videos) has seen it happen on a guys boat. He was able to clear it by manually overcharging. The information is out there but like everything else LiFePO4 searches will give you the wrong information we are fed. You need to read the scientific literature. You might start the search with Conrad's article linked to the bottom of www.emilyandclarksadventure.com/bbms He has links to research

[@jeffoneill3429]

No really, does anyone have a source or further reference for this claim? Cheers.

[@Clarks-Adventure]

Go to Google and do a search if you want to know. I just did a 2 minute search and found this. www.researchgate.net/publication/275403167_Failure_Investigation_of_LiFePO4_Cells_under_Overcharge_Conditions It's not one of the papers I remember reading, and no I didn't just read it. The important advice I offer for your research is you have to skip the shiny marketing pages from the battery salesmen and read the scientific papers. It's the 21 century. The information is right out there, you just have to ask a search engine. I hope you have a fruitful search. It's eye opening but a little brain fogging to study this stuff

[@dssque1]

@@jeffoneill3429 google LiFePO4 hysteresis. lots of memorable reading

[@evanmayer744]

I have not come across any direct evidence for this claim in years of research and testing. However, degradation of any kind causes higher internal resistance - and since IR rises as you approach 100% charge, perhaps people are mistaking degradation as a "memory effect". In practice, the more you keep a LiFePO4 cell away from SOC extremes (>3.45V and >2.5V, where the most degradation occurs), the BETTER it will tolerate a charge to 100%, courtesy of the lower baseline internal resistance.

[@preacher031163]

Not only do u ramble this is supposed to be about NOT LEAD BATTERIES...some of us have a hard time keeping signal ya know

[@moonhand8311]

This video, amongst other positive things, shows why LiFePo4 is a nightmare of complexity to you averagage user. This is why 'non specialist' people have to buy black boxes, fit and forget, and not really have a clue about what's going on! One other thing for sure: hybrid (LA mix) is a must for any boater.

[@Clarks-Adventure]

Yep. That's why I developed the BankManager. For LiFePO4 users who wanted to do it right but not necessarily manage them themselves

[@gerardbarra4127]

I only use my trolling motor for maybe a couple of hours each time I fish. Should I top off my two 12 volt the theme batteries or weight until I use them several times.

[@Clarks-Adventure]

A theme? I'm going to assume you meant lithium. Don't top them off. Just make sure you leave with enough power for the days mission

[@gerardbarra4127]

Thank you. I also just noticed weight in lieu of wait. Voice recognition not great

[@trevortrevortsr2]

We call it the knee, not "hockey stick" in Europe & Australia - We charge them in 2 main stages Bulk and Absorption - typically on a 100ah Bulk charge for 14.4v and when that's is achieved absorb for 2 hours at 13.8v - some times you can charge what's known as lithium light where the bulk charge is lowered to 13.8v

[@Clarks-Adventure]

I feel sad for your batteries

[@HybridShedIraq]

Thank you very much. I can confirm the memory effect. I've been charging batteries to 54.6v, and now they take no power more than 54.6v.

[@surfingcuriositywaves4046]

You asked if any of us knew of other chargers that use the larger 'information set' that is required to accurately monitor state of charge and acceptance rate of charge. I believe that I saw a video by the developers of the Wakespeed alternator controller that uses a lot of information from the CAN Bus to determine voltage output of your alternator. There is a competitor (not Balmar) that also claims to use sophisticated feedback, but I cannot remember their name. However, these competitors are operating through the alternator, and may not smartly control other inputs like solar panels.

[@rpgreseller]

One situation in which it is beneficial to always charge your LFP battery bank with wall current is for security guards first responders who simply are trying to have lots of current available for either 12 volt devices or other devices that they would run using an inverter and they are trying to save on gas. They don't want to use a DC to DC charger to recharge their battery bank. They want to go home at the end of every night, plug it in, and get cheap electricity.

[@Clarks-Adventure]

Sure. I'd plug in if I could. But lots of these are used off grid and actively used while charging

[@nickjohnson410]

Showed up to make a joke about the dangers of Dihydrogen Monoxide. Stayed for the in-depth talk about battery charging.

[@scottdeyoung249]

Two questions- 1) what is the disadvantages to “keeping topped off” 80% to 100% most of the time? 2) if charging often midrange, say 50% to 70% or 40% to 60%, would it be better to not charge at all until able to charge to 100%? Ok three questions😂- in both short charge examples, is this considered a cycle to the life of the batteries?

[@Clarks-Adventure]

I'd check out that video I linked in the description for the first answer. But in short cycle life I think if you charge to 100 now and again you are fine. Li isn't as sensitive to this as lead is. Different animals I think life is best expressed in total watt hours delivered not cycles but things get dumbed down. Again I didn't go into this as the engineering explanation guy did a good job

[@ducatiduke]

Granted more expensive, but I wonder if it would help to have two systems, albeit connected, to switch back and forth to. That way you could isolate one system to use while the other one gets properly charged

[@Clarks-Adventure]

If you are charging with alternative energy sources you would still need something like the BankManager because the charging amps aren't constant. And drawing power from a big bank is better than from two small banks in sequence. Lower amps per cell

[@josephlarocca531]

Hey Clark! ...I ONLY have LiFePO4 batteries (3) on my sailboat 400 AMP hours at 48 Volts. QUESTION: is the BankManager the BEST product for regulating changing these LiFePO4 batteries. Keep in mind I also have 1. Wakespeed Alternator regulator for my 48 Volt 100 AMP alternator. 2. onboard Inverter / charger . 3. Victron MPPT Solar battery charger. 4. BMS systems on each of the LiFePO4 batteries. Question: If the BankManager is the BEST product for regulating changing these LiFePO4 batteries then HOW best to install it and easily (DYI) integrate it and WHERE. By the way I have a foolproof way to find a stunning, captivating, enjoyable, with a lovely full time sailing Partner that will respectfully obey your wishes with her whole heart and with a great positive attitude. My buddies' and I used this system successfully 20 + years ago and we each have the best petite feminine respectful full time sailing Partners on our boats.

[@Clarks-Adventure]

First off I want to know about your method of course but I'm thinking you are talking about a dog as a companion 😊 Yes, all those charge controllers charge to a voltage. The BankManager is the only system currently available that charges "right". Epoch recently tried to solve this problem with their BMS but missed the mark by a long shot and ended up spoiling their reputation. It's a hard problem to solve and they took a shortcut. As to how to install it I suggest you read this page and especially the BankManager manual www.emilyandclarksadventure.com/bbms Or if you want detailed personal help I have a Patreon tier called Dream Believers which gets you phone meetings with me. As an aside. Are your 4 batteries 12v on series or 48v in parallel? If they are in series you should run a battery balancer between them I have an inexpensive one on my Amazon store in the Duffy section.

[@SiegfriedReuter]

Good video, Learnt a lot. Where can one acquire those bank managers and where can one get a hold of you directly. ? Cheers SR

[@Clarks-Adventure]

Thanjs All that is in links in the description. MarineDCAC.com gets you to the engineering I've been developing. There is email. But if you want consulting that's the Dream Believers tier on Patreon.

[@mm-zw1zc]

excellent review, but i would point out a couple of oversimplification statements made. i have been off grid for past 2 years and have a lot of lifepo4. I do charge it essentially the same way Clark describes, but do not use a bank manager. How, and how do i know? My equipment is SolArk inverters, and SOK batteries, but i monitor with software (Solar Assistant) so i know the voltages and currents in real time. With sol ark at least, but i presume other good inverter/controllers, the chargers are not as simplistic as Clark describes, and have various modes and set points. For example, i use a voltage mode, but i know the voltages exactly because i can watch the hocky stick in real time. i have a large battery bank that keeps the loads low and relatively stable compared with capacity. I set the voltage cutoff at the begin of the ramp, and let it ramp higher once a month. So the small quibble's i have with statements made here are that 13.48 is where the ramps are. Not on mine. different batteries are all a bit different here. The battery mfg should be able to provide values for floats and absorption but a monitor can help you determine this. Also good charge controllers do seem to charge correctly, and i am pretty sure Victron has products that do this right.

[@Clarks-Adventure]

Thanks but I disagree on a few points First I said 13.48 is where the damage can start in a FULLY charged battery not the hockey stick. Second, once you are in the hockey stick voltages you are already fully charged thus seeing damage. Third, fully charged can happen at any voltage from 13.48 up. So charging needs to stop based on the situation the battery is actually in. Good on you to let them overcharge now and again to balance the cells. Do you monitor to know how often you should do this or did you just choose once a month?

[@mm-zw1zc]

@@Clarks-Adventure I agree with your point that this is a complicated discussion. The difference for me is that I have a 164kwh bank, and its in my basement which has stable temperatures. The C rate is so low that voltage turns out to be very predictive. The bms "state of charge" will drift off over the course of the month, because i can cut off just before its "100%". For me this is 55.2V. I float after that at 55.0v, with nearly zero current. The inverter will limit solar inputs to power loads+what ever extra goes toward the batteries. The bms will read 99%soc, and drift lower but the reset at 55.7.

[@Clarks-Adventure]

@mm-zw1zc yep it sounds like you have things under control with your system.

[@kristiannyblom7847]

Dear @mm-zw1zc, I am curious, about where you have found any information about "float" and "absorption" voltages for any LiFePO4 batteries. Maybe I am wrong but those concepts are only relevant to Lead-acid chemistry. You are referring to a voltage start for the "hockey stick" and if I understand you correctly you believe this is a constant irrelevant to the history of the ongoing charge cycle? This is not how I understand the concept of how you arrive at a situation where you are really close to 100% SOC and at the same time not likely to go into a low current overcharge producing metallic lithium rather than storing usable energy in the battery. Why do you think a hockey stick voltage rise exists in Lithium? If I would try to understand with water analogy that is often used in electrical things ( but not always relevant) I would like to imagine a full bucket of water where if you have a larger/ faster inflow the bucket will overflow earlier compared to a really slow drop after drop where the surface tension of water actually visibly can be seen forming before said surface tension breaks and water starts overflowing. Just as an analogy model to understand low current overcharge in the drip scenario, the bucket contains more water molecules compared to the fast fill scenario. I think there is a lot to learn and verify over time about this relatively new chemistry and I have been interested in the subject since 2009. A comparison might be concrete where MIT has been trying to recreate and copy some things done during Roman time that have by now been thoroughly tested!!.. fun and fascinating on the concept of the devil is in the detail! My take is that Clark is very well-read on the finer details of LiFePO4 chemistry as far as science has described it up until today. I like a guy who can admit that he has changed his mind about finer details and adopts his invention/recommendations accordingly. My take is that Victron et al are a bit surprisingly not really at the forefront of things and that this is just a business/ profit/ production decision. It is not like they are getting the upside of maximized life out of these cells but more "good enough and charge a higher relative price due to brand logic".

[@peregrinatorperegrinatorx7108]

My MPPT does everything your little black box does and more, so if worried buy a better quality MPPT, it has three ways to charge, you have a choose, volts, amps or wattage, job done.

[@Clarks-Adventure]

Does it watch the amps actually going into the battery, not the amps leaving the controller? What happens when you turn on a load while charging Then you have to compare the algorithm. For example EPOCH just tried this in their BMS and failed terribly.

[@markthompson7288]

Have an older motorhome. Would like to change house batteries to 48V lithium system and keep chassis batteries 12V. Will your bank manager device work with that setup?

[@Clarks-Adventure]

It will protect your new 48v Li and control it's charging but no it won't step up/down the voltage. You would need a boost converter like Dc-Dc charger for that part.

[@kishanmajethia]

​@@Clarks-AdventureI have a car with LFP battery. Whats the best way to charge it?

[@Clarks-Adventure]

I think the BankManager of course and something to keep the charging C rate under control

[@kishanmajethia]

@@Clarks-Adventure lfp cars manual says to charge to 100% atleast once a week using slow charger (either 3kw charger or 7kw charger). It helps in removing memory effect + soc calibration + cell balancing.

[@dtrguy2707]

Hey Clark! When not using the batteries daily and plugged in to shore power with a Victron main charge/inverter (and a hybrid system using your BBMS) I’ve started putting the system at max 80% and min 80% to keep it from needlessly going up and down every day. I’ve seen cycle counts in Bluetooth for each battery even when not being actually used. When. Unplug from the dock and sail I raise the charge to 100% max and min to 20%. Thoughts on this? Lithium is 500ah and lead is two group 24 (80x2ah).

[@Clarks-Adventure]

I'd set your dock settings to 80 and like 40. The BMS is a stupid beast I would use it's cycle count with a grain of salt It's likely to count ANY charging as a cycle. The BankManager will allow a li bank that is not a candidate for recharge to go up to 13.45v before disconnecting.

[@Ben-ry1py]

Do a separate video on lead batteries or at least put in chapters so we can get to the subject of the title please.

[@Clarks-Adventure]

I think chapters is a good idea. I'll do that soon

[@MrPbologna]

How do I buy the bank manager device? Will it cut off Lupo batteries wo a low temp sensor? Will a Victron BMS shunt do the same?

[@Clarks-Adventure]

I don't know what lupo means. please type more carefully. BankManagers are available at www.emilyandclarksadventure.com/bbms And there is a lot of information there.

[@o.g.solutions]

Midnite solar, the kid , charge controller, ,is designed so you can charge all the batteries. It is infinitely controllable and every metric is user adjustable

[@toddtavares7386]

Clark, how do we know when we've discharged a LA battery to 50% (or 60 or 70%?) I've seen in discussions on boating electrical Facebook pages where people say a 12 volt LA battery is fully charged at 12.65 and 50% discharged at 12.0 volts. What reading, or how do you determine a battery is 60 or even 50% discharged?

[@Clarks-Adventure]

Let it rest with no charge or load for 24 hours (2 hours works ok usually) and check its voltage. Then use those tables 12.0v is 50 percent, 12.8v is 100 percent. The resting is vital and the table is only accurate for new healthy batteries

[@denameier1442]

I have a 5000 Watt Growatt All in one charger inverter with a 280 amp hour 48 volt LiFePO4 bank. No lead acid battteries used, and don't intend to ever use lead acid. 200 A, 2A balance JK BMS used. Can the Bank Manager be used with this setup?

[@Clarks-Adventure]

You need some lead especially with growatts as they switch slowly. The lead is there to keep voltage under control when the li is removed. But if your system is smaller then this you likely could get away with 4 starter batteries. kzbin.info/www/bejne/pYiaeJWPiZiimdE

[@patricklyons7683]

You should of had two demonstration rigs, which you show adding the 'bank-manager' device & its Bluetooth or control system. Holding the kit up doesn't do if justice imho

[@cs6-n3p]

👍

[@NatTate-f7e]

Add a GPS function to the weather report blackberry so that it KNOWS where it is. And be able to bypass that if we lose GPS ability.

[@Clarks-Adventure]

Yep And a bunch of software The Gen 3 has an external pin called reset. Force it low and it's like pushing the reset button

[@NatTate-f7e]

@@Clarks-Adventure I think I meant raspberry. But by bypass, I mean be able to insert a zip code or Lat Long location to work if GPS function goes away. But if GPS goes away, we may not have weather reports either.

[@Clarks-Adventure]

Yep. Sounds like what the guy is working on

[@toddtavares7386]

Second question. If someone bought your Gen 3 BMS, do you include a power dump resistor... or do you indicate a resistor rating?

[@Clarks-Adventure]

No I leave the load up to the user. Like 2 ohms with a proper heat sink is a good upper limit. Maybe 4 ohms

[@jeffdege4786]

You have three Battery Bank Managers for three separate LiFePO4 banks? Does that mean you have three lead acid batteries, paralleled with the three banks? And that the three banks each power distinct circuits on the boat?

[@Clarks-Adventure]

Good question I wasn't clear. I have 3 Li banks all connected to the 1 lead bank and one distribution system The BankManagers bring the li banks in and out as necessary. It's interesting to see how different the three banks operate. One can see that if they were put together they wouldn't be happy. But since the BankManager only cares about the li bank it's responsible for each bank gets its own special treatment

[@jeffdege4786]

@@Clarks-Adventure I like the redundancy of multiple banks, but the complexity of managing them and switching between them worries me. AIUI, you have one house distribution system powered by one LA bank, with three BBMSs each switching in a different LiFePO4 bank, when it feels it appropriate. That seems like a pretty nifty setup.

[@Clarks-Adventure]

@jeffdege4786 yes. I knew it would work of course but once I actually wired it up I saw a few extra little advantages. For example while I go into the menu on one the system lead is held to Li voltage by the others so when I leave the menu the BankManager I worked on connects its li back in right away. And in my case I can see one brand of battery has a lower resistance and gives up/accepts power much faster than it's neighbors. (VoltGo)

[@rdpackett]

I have a bluetti power station, any thoughts if BLUETTI truly charges to 100% or is it really charging to 80%? For long storage they do recommend to store at 80%, how advanced is BLUETTI electronics? since it’s known to be one of the best brands.

[@Clarks-Adventure]

The bluetti I've used has LiFePO4 cells but make sure yours does. If it has another kind this doesn't really apply the same way. I'd bet the farm they overcharge a bit each cycle if you let the thing sit under charge power.

[@marcobrian1619]

Brilliant talk about lifepo4 battery But does this go for DIY packs of cells. IV just got a 48v server rack"new" with eve 280ah cells, IV broke it down to make 2 24v packs.... I'm currently top balance all cells (8 at a time). But IV just had a customer ask me to look at his server rack....goes from 100% to 20% in about a hour...,.... Same again.....cells not balanced so BMS was seeing one cell hitting full and stopped charging then saw another hit low so shut down ....... Now all fully balanced.....works perfect.

[@Clarks-Adventure]

Yes you should charge any LiFePO4 this way

[@paulfitzgerald1466]

Thanks Clark, lead carbon is looking better every day….

[@barneycarparts]

I want to charge a 12v LIFEPO4 6ah battery on my solar tracker from a 35VDC panel. I thought about using a LM7815 15vdc voltage regulator for charging. After this video I see I can't do that. I never imagined LIFEPO4 were so particular. We get 5 days a year below 32F so I think I'll have to go SLA AGM lead acid. Instead. I wish I watched this video earlier. Now what to do with my 2 LIFEPO4 batteries and 2 LIFEPO4 smart chargers? Maybe I can make a under water robotic pond sweeper.

[@baneverything5580]

I paid 1200 bucks for my 300ah 12v Ampere Time. I have a slow 300w LiFeP04 wall charger, a 500w LiFeP04 wall charger, and 3 solar charge controllers for solar. I recently got 2 Victron 100/30 ones with LiFeP04 settings but haven`t wired them up. No hurricanes yet here. I keep my 3.8 kwh capacity battery charged to about 3.3 kwh. I fully charge, then use my 500w window ac for one hour. We have lots of random power outages in Louisiana and the battery can run my window ac all night with the thermostat set properly.

[@Clarks-Adventure]

It's good you aren't leaving them on charge. Stand by power like yours is easier to work with than an active system. I think your current charging plan is better than what the Victron will do. Also you might benefit from looking up the charge plan used by industry. Basically charge at a constant C rate until a voltage is reached then stop charging. That voltage is defined by the C rate.

[@stevenshircliff393]

Excellent presentation! But I'm confused. I have 2 48v 70 ah lifepo4 batteries connected in parallel that I use strictly for emergency backup. How should I keep these charged properly?

[@Clarks-Adventure]

If you want longest life leave them at 50 percent But what's the point of that. I say charge them to full put a tiny load on them to bring the voltage to 13.4x4v. And keep your tank full for emergencies. That's their job after all

[@stevenshircliff393]

@@Clarks-Adventure Thank you!

[@corbinschad1]

So what is wrong with charging at 3.5 vpc, absorbing till and end current of 5% ah of the bank, and then float at a point that just keeps the house running?

[@Clarks-Adventure]

If you charge at a low C rate, which is very common with a big bank charged by solar, you have already overcharged at 3.425v per cell. That's why its called "low current overcharge". It damages cells Most days my batteries finish at 13.8v

[@corbinschad1]

@Clarks-Adventure thanks for the reply. I was hoping you were going to cover some of that stuff in this video. You never really stated what the bank manager is doing, just that it uses an algorithm. Maybe a second video. Guess I have some reading to do. My system can do .2-.3c depending on weather of corse.

[@Clarks-Adventure]

Yep I could have done a better job. Today I rewatched it to put chapter headings in. That should make it easier to jump to the good parts. I think I do talk about that but not as well as I should obviously. Now that this one covers the ground work maybe I should do two more short videos. How to charge... How to kill... LiFePO4

[@brainstorm3446]

Some of us don't have solar because we live in apartment, so the grid is the only way to charge!

[@Clarks-Adventure]

That makes life easier. But I don't see the point unless your local power goes out a lot

[@Actrealsurprised]

Why don’t they have balance leads like my lipo batteries for my rc cars. Or is that pretty much what a bms built in the battery does ?

[@Clarks-Adventure]

It's what the BMS should do. Some aren't great at it

[@crw-bm7mm]

As soon as you tried to flog your product, I had to take everything you said with a huge grain of salt. I will stick with people like Will P. with no other motives than sharing good info.

[@Clarks-Adventure]

As you like but realize Will is not an engineer. And he profits heavily by pushing any battery he's paid to promote.

[@paulpozboater]

Hi Clark, will the Bank Manger plus take the place of a BMS in a home built battery? Thanks

[@Clarks-Adventure]

No. They do completely different jobs. The BMS job is to keep the cells from destroying themselves The BankManager is more about charging properly and mixing in lead batteries

[@jasonmcintosh2632]

"you shouldn't put [different lithium ion batteries] in a parallel bank, but you can put them in separate banks that are in parallel controlled by their own bank manager." HUH?

[@Clarks-Adventure]

Yes. The BankManager charges each bank to its own needs. For example in my system my VoltGo accepts charge faster than my Redodo. (Both about 400ah). So if they start at the level of discharge the VoltGo BankManager will switch out first. Then the Redodo will finish its charge and switch out later. If they were in parallel the VoltGo would be held at high voltage even after it was fully charged damaging its cells. I hope that example clarifies

[@jasonmcintosh2632]

@@Clarks-Adventure I'm working my way through your version 3 manual. Does your BBMS have a bluetooth connection and a cell phone app? It looks like you've done some great work. I haven't put lithium batteries on my sailboat yet as it's in the Galveston area and I don't plan on starting cruising until 2027... I have roughly until then to figure this stuff out... Thanks for a great video.

[@Clarks-Adventure]

Bluetooth yes. App not yet but I hope well before 2027

[@olafschermann1592]

JK-BMS uses active balancers. Kinda standard BMS in the 16S / 51V world.

[@Clarks-Adventure]

Yes I did a build video on their BMS. It's my favorite!

[@markreynolds8630]

So, 2 BBMS would mean 2x contactor switches?

[@Clarks-Adventure]

Yes

[@galaxyb1103]

I understand your concept but these lifepo4 batteries already have bulit in BMS, under and over charge protection. Why do I need yet another device to regulate charging when there is already one fitted by the manufacturer inside the battery, for this specific purpose?

[@Clarks-Adventure]

I suggest you watch the video again. The BMS only stops charge once the lead cell is about to actually vent electrolyte. Damage is happening at that charge level. The BankManager can stop charging at 100 percent. This is vital to long cell life. Loads of academic papers on this. But the battery manufacturers are only slowly talking about this. They are getting so many warrantee claims they are starting to take charging seriously but since they don't know about the BankManager they are trying to do this in the BMS (EPOCH) and failing miserably

[@laurapitre5797]

So how many white papers have you read that recommended using lead acid with lifepo4?????

[@Clarks-Adventure]

Just the ones I've written including the one the ISO asked me to write.

[@el_sweetime]

Hey Clark I have a 3 power queen 200ah 12v batteries I noticed that one of them has a rattle when I shake it. Wondering what your thoughts are and what I should do Thanks for the help

[@Clarks-Adventure]

? Don't shake it You can look at my view video to see what you guess has come loose and if you think it would pose a problem. It's probably fine

[@amerkhafagiable]

How come many car audio fans charge their battery bank (high C rate) directly from alternator without any device as dc-dc charger ?

[@jasonmcintosh2632]

Oh, I got another question... I watched another video where you said that your bank manager won't connect the bank to the lead batteries if there's a significant voltage difference. Suppose you're in the condition that they're disconnected and the lead batteries are supplying a small load. Then some big load occurs (microwave, air conditioning). Is the bank manager fast enough to connect the managed battery bank to the lead batteries as the lead battery voltage drops suddenly? I suppose the answer to this must be "yes"...???

[@Clarks-Adventure]

Yes it's yes. Some of the early software could miss occasionally, but I put a fairly brute force algorithm in that seems to work much better now.

[@ΒασίληςΤ-υ1μ]

Hello Mr Clark, from which store can we buy the BankManager you have ? Thank you, Bill

[@Clarks-Adventure]

Ask again in about 2 weeks and it should be set up.

[@ΒασίληςΤ-υ1μ]

@@Clarks-Adventure Ok thank you !! I have 3 baterry banks of LifePo4 48Volts, parallel connection 16 cells each !!

[@kevindewinter8235]

I hope your BBms wil be available in europe. Ps i ordered Some lithium titanate cells since its advertised as very save. Do you have any tought on the LTO’s? Thank you

[@Clarks-Adventure]

It is and I sell lots of them there, but you need a US address If you don't have a convenient American friend you can use Reship.com to take care of the import for you www.emilyandclarksadventure.com/bbms

[@vikp6115]

Weird my charges are charging lithium to 14.7 thsn disconnects and it trickles ?

[@Clarks-Adventure]

Ouch.

[@HotRockCentral]

You're wrong that you can't charge LiFePO4 to a certain voltage. I have my chargers kill charging at 27.1v on my 24v system. 29.2v would be 100% & 27.1 is just past the upper knee & even tho The difference looks big, 27.1v is only about 2% away from full charge.

[@Clarks-Adventure]

You are causing a memory issue to develop and the target voltage has to be modified by c rate at the very least I contend you can't charge li properly to a voltage. But of course you can put power into them that way.

[@rogerstarkey5390]

"You can abuse a Lead Acid battery" Errr... NO. If By "Abuse" you mean discharge below 50%, you certainly CAN'T

[@Clarks-Adventure]

Watch the video again. I didn't say that

[@johnbianchi3877]

Maybe just not use these firebombs in the first place. I plan to live without them as I have for the past 20 years.

[@Clarks-Adventure]

As you like but I personally feel you are missing out. And LiFePO4 just isn't as subject to thermal runaway as other li chemistries. I personally only will use or recommend them After on a boat you never want your big decision to be will you burn or drown?

[@fixitpro]

If I wanted to learn about 'lead', I would have watched THAT video..

[@Clarks-Adventure]

Sometimes to explain a complicated subject one must lay ground work first.

[@jamesmartello4428]

Can I use two bank Managers on the same lead battery (want to add new lithium to my existing set up).

[@Clarks-Adventure]

Yes. Sorry I wasn't clear. That's exactly how it works Just another Li bank wired in parallel to the lead with a BankManager contactor in the positive wire. Freeze frame on my video and you should see that the left side of the contactors is a copper bar with one big cable going to lead and the boat

[@jamesmartello4428]

@@Clarks-Adventure Thank You

[@station247365]

I bought li-time lithium batteries along with their charger. I have always used the charger to top off/full charge the batteries. Is it hurting the batteries 400 ah in series for my van conversion? Do I need to turn off the solar occasionally?

[@Clarks-Adventure]

I'll look later most likely as liTime is currently sending me their newest battery for review. But every other "charger" supplied by battery manufacturers I've seen was just a 14.6v power supply. Arguably the worst thing you could use to finish charging. If it looks a lot like a laptop power supply. It's that kind. They are the cheapest way to put power into a battery so they sell them. Easy profit.

[@s.mendez7160]

Take a look at Li-Time's charger profile that supposedly pairs with their LFP Batteries.

[@Clarks-Adventure]

@s.mendez7160 I'll give it a look when I get home.

[@Clarks-Adventure]

If you mean something like this www.litime.com/products/litime-12v-10a-lithium-battery-charger Yeah, it's crap

[@station247365]

@@Clarks-Adventure Yes that's the one I got. Which one do you recommend?

[@joeblaney684]

You have my trust and I suspect most of your viewers so it’s ok to go to outcomes and skip the why. So put a chapter people like me to skip too that way you can satisfy those who love the education and those who need to get the result faster it’s too long for this medium. You’ll lose views the further this goes the less I understood the point

[@Clarks-Adventure]

I might add chapters. Good idea

[@ThanosSustainable]

Unfortunately, there's a high number of wrong information in this video. Oh, this was a product presentation... now it makes sense.

[@rsalvaterra]

So many!

[@mesuddzomba7849]

Hello, I just installed two lithium Lil Time batteries for my 24V trolley motor ( 2X12V in series). Both batteries are ( brand new) fully charged and balanced ( smart app ) Both batteries are over 13 V .Under the load of 24 V trolley motor voltage is instantly dropping in negative voltage. One of the batteries ( bank 2) instantly losing voltage. It looks like is in reverse polarity which doesn’t make sense to me. batteries are correctly wired in series, In good condition and nothing wrong trolley motor( not powering up at all). Does anyone can point me in right direction, what’s happening? I am confused.

[@Clarks-Adventure]

Am I correct on assuming you don't have a multi meter. Solving things like this are very difficult without one. I suggest this one. kzbin.info/www/bejne/oavZgoCdnqmGo8U It could be a failed BMS. Or a bad connection

[@mesuddzomba7849]

Hello, Thank you for the swift reply. Yes, I do have multi meter. Under the load of trolley motor one of the batteries drops in negative voltage numbers and motor wouldn’t start( needs 24 V ) Before the load both batteries showing fully charged and over 13 V. It’s like battery is discharging under the load. This is a brand new smart batteries out of the box. Bluetooth app shows that both batteries are in good order and balanced. I have limited knowledge in this field but this is mind blowing for me. I just don’t understand

[@Clarks-Adventure]

@mesuddzomba7849 seems like you should start talking to the battery manufacturer as a replacement is likely in your future. Voltage reversing would happen of the BMS of the bad battery switched off or if there is a real bad connection, possibility inside the battery. Think of it this way. The bad battery becomes a big open/off switch. You are actually seeing the voltage of the other battery read through the motor.

[@mesuddzomba7849]

Great explanation but why is the battery testing good ( v, amps and bms )prior to load? Like I said, I have very basic knowledge and this just blows my brains out..lol Your help is greatly appreciated, mentally wise…hahaha

[@Clarks-Adventure]

@@mesuddzomba7849 well I'm not there. But you can't test certain things until you apply a load. It's failing as soon as you apply a load

[@Dkrpan59]

How about the other end lithium ion batteries

[@Clarks-Adventure]

Maybe you need to type this? I don't know what you mean

[@kishanmajethia]

I have a car with LFP battery. Whats the best charging strategy as per you? I discharge it till 20 to 30% and charge it back to 100%

[@Clarks-Adventure]

I think the BankManager of course

[@kishanmajethia]

@@Clarks-Adventure we cant use bank manager in cars. We have warranty to take care of

[@Clarks-Adventure]

@kishanmajethia yep I understand There is a guy with a crazy expensive new motor coach who went BankManager He put the batteries and BankManager in a box that connects with a big Anderson connector When he takes it in for service he just unplugs it and removes the whole Li system.

[@PazLeBon]

The sun dictates the charge rate lol, for most of us buying into it nowadays

[@Clarks-Adventure]

Yep. Charging LiFePO4 would be so much easier if we always had will plugs. But of course if we had wall plugs we likely wouldn't need batteries

[@NaturalHerbsForHealth]

Learn to stick to a topic and straight to the point this video couod be under 3 mins but Toomuch beating as round the bush 🤦🏾‍♂️

[@Clarks-Adventure]

I'm looking forward to watching your version

[@EddieC5715]

Why is it so hard to find the price fir your device ?

[@Clarks-Adventure]

Are you looking here? www.emilyandclarksadventure.com/bbms/buy The description starts here www.emilyandclarksadventure.com/bbms And you just click on "buy now"