DIY SOLAR Battery Banks - Parallel? Series? Both??: What, Why & HOW! Beginner Friendly

An in-depth HOW-TO on Parallel VS Serial Battery Bank configurations for people just getting started in Solar battery storage.
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[@danielgjb]

Want to make a comment without sounding like I am criticizing. I have worked as a mechanic for years. Best safety advice when working with batteries. To avoid shorting the terminals when connecting or disconnecting batteries. When connecting Always connect the Negative terminals last. When disconnecting Always disconnect the Negative terminals first. Less chance of accidently making contact with the metal wrench and causing shorts.

[@mikeshivak]

Yes

[@lynnlivermore6777]

Like your presentations, do you have any presentations showing how to set up a shore power application added to this presentation? Thanks Lynn

[@jacobcarlson4010]

@danielgjb: That’s definitely true when you’re under the hood of a car; in that situation, everything that’s metallic but not painted/insulated or isolated by an electrically insulative material (that one is very uncommon), will have continuity to the negative terminal lead. So in that situation, yes; connecting the negative lead last will matter. However, that’s not the situation he’s in with this video. And in fact, I don’t know many people that are putting their battery banks in metal enclosures that are “grounded” to the negative terminal of the battery bank. Most setups I’ve seen have been wood, since that’s a lot cheaper and doesn’t usually require insulating every metallic component around the terminals to guard against arcing during high load. TL,DR: You’re not completely wrong, you just overlooked the fact that it’s a different situation which renders the advice mostly moot.

[@sreekumarUSA]

@ Danielgjb,>Please, what are you talking about? This is LiFePo4 system. And the gentleman is talking about 2X 12Vdc in Parallel and series configuration. Where does the Negative terminal connection to be connected last, idea come from? We are not talking about Studebaker, DeSoto, Plymouth, Holden, Oldsmobile, Model T. He has a CB wired and that was @ OFF condition when the Battery was connected. Hello this is year 2023.

[@koollee]

@sreekumar .. Lol!!

[@davidpotter9462]

I used twenty big marine batteries. They're in 24 volts hookup. I used #2 welding leads on all battery connections. I have been off the grid for two years. I used an Aims 2000 watts inverter charger, 24 volts. I have 1400 watts of solar panels. I also bought a 600 watts wind generator last November. It helped a bunch last winter. I'm showing 24.8 volts at 6 a.m. I think I had six batteries when I bought the Aims Power inverter charger. It didn't start acting right until I hit 16 batteries. It's working good now with twenty. I had one battery go bad last summer in the heat wave. I couldn't get to it to check the acid in it. It shorted out and I replaced it a few months ago. I had to buy a 31 series because they don't make the 29 dp-dl anymore. My setup works okay. I ran the air conditioner off of it four hours yesterday. My inverter has a dip switch that changes the low voltage setting from 22 to 24 volts. I don't use the higher setting. If the voltage drops below 24.0, it wants to turn the charger on. I think that setting is for the batteries like you're showing here. I use the lower setting so that I don't need the gas generator. I have 25,000 watt hours. I built my system to run a small house or cabin. And to let me be able to build one. Well I enjoyed reading the comments. I'm at that point. I have enough batteries to go to 48 volts, but probably won't. The inverter would cost too much for me. Im on social security. And I would need another charge controller to have any more solar panels hooked up. Im using a 4215 BN , Epever 40 amps, 24 volts. Im pushing 34.5 amps through it around noon or one. Adding two more panels would put me right at 40 amps. Id rather not run it right on the edge of overload. The inverter charger Im using has went up from $769 to $995 since I bought mine. I had a 15% off coupon and mine cost $653. I had to replace the power and control boards in it once, after I ran a welder with it building my wood stove. I bought a Winco Lil Dog 3000 generator to run the welder after that. Well I got to look at the insides of the inverter charger. It has a heavy transformer. I thought maybe it could do it. I blew the tops off of five of the MOSFETs. Cost me about $400 to fix it. It's been working okay the last year and a half. I replaced the temp sensor in it too. It has to be in one exact spot to work right. Even if you turn it just a little bit, it changes how it acts. I was going to get a 3000 watts inverter but they were sold out of them at the time. I thought a 4000 watts was too high. And they're split phase. I've gotten used to this old single phase. I have a spare 2000 watts inverter but it's 12 volts, sucks amps. I use it in the pickup once in awhile. It doesn't matter about the amps, I just leave it running. I bought a bigger battery last year and enlarged the battery box a little bit. I put a 900 amps battery back in it. It works pretty well with that inverter. It just rained, clearing out, my system is making 789 watts.

[@meilyn22]

Nobody explains it like you do. You are the best at explaining stuff.

[@Bobbel888]

Finally some able to discuss battery topologies. Thank you very much!

[@Mike.Caimbeul]

Another excellent explanation. As always, straight forward without any nonsense. Many thanks.

[@TheVikingSasquatch]

Think I'm gonna attempt a diy for camping and power outages. You're info has been the best by far.

[@ReeWrayOutdoors]

Thanks for the kind words! Sincerely appreciated.

[@TheVikingSasquatch]

There's a good chance I'm going to have some really stupid questions. 😆

[@roysmith7087]

This looks shockingly simple to do ⚡💡

[@martingingerich8830]

Your Humility just adds to this great video...

[@timsmith4970]

Thanks it was well presented and easy to understand 👍

[@ronaldjorgensen6839]

thank you for your persistence each one

[@garytrawinski1843]

Excellent video! I like to tinker with stuff. This video will be helpful when I build my own portable system.

[@t.d.harris1311]

This is the one I have been waiting to see, great job explaining this subject. Thanks... I plan on using an inverter with a built in charger.

[@arksonephimmasane5134]

Thank you for sharing and very educational!

[@kevinrey9427]

Very useful information. Thank you!

[@user-pu4fl6dy9u]

Well done, makes total sense. Very much appreciated Thanks

[@danielchukwu5062]

I really appreciate the effort you have put I making this video it the best of all it series on KZbin ❤❤❤❤

[@SeanInAlaska]

Awesome explanation! Thank you.

[@ImASurvivorNThriver]

Great video! Thanks for sharing.

[@jackas1583]

God bless for teaching n solving my 2 battry setup...

[@Ricardofromage]

I'd had a read through on line about a 2s2p set up, my mercedes vario conversion is a 24v system to start with, so it just made sense to stay at 24v, elastic trickery has never been my strong suit. Hearing the systems explained in layman's terms is really useful, thank you for a great video, I confirms what I'd already read, but being a nervous kinda chap around electrics, having the confirmation in layman's terms is awesome, thank you

[@timturman8624]

Very easily explained brother job very well done

[@240zron]

That was one of the best, easiest explanations I have heard. Nice job explaining

[@ReeWrayOutdoors]

Wow, thanks!

[@alnear4953]

​@@ReeWrayOutdoorsHey great video as always..! Was curious if you have one on how to run 120v off of battery banks, either 12 or 24v setup that would run a 30amp AC unit in an RV..? Just curious if this could be done with 2 batteries or would I need more..? Thanks again and keep up the great work. Much appreciated..!

[@Wugawamp]

This is excellent information. Well explained for a beginner (like me) to get started. Subbed. Thank you.

[@usmcgunz1066]

Great video. Thanks!

[@rejangguy]

One of the best explanation. Thank you sir👍

[@millzee60]

I was hoping you'd be explaining why many of these drop in replacement battery manufacturers state that their batteries may NOT be connected in series/parallel.

[@TZ-zf1lp]

Great information 👍

[@jacosmith7039]

Awesome info man

[@rl5271]

All good and clear info. I'd like to see more about wire size to use, crimping tools and method. Many thanks!

[@junaidali6697]

Nice demonstration

[@mannys4036]

There is no doubt that your explainations are the best. I love the pace at which you explain the details. You never rush; you are clear and concise. After viewing any of your videos, I walk away with more understanding than I do with channels with similar content. I watch many wonderful KZbin channel that do all sorts of product reviews and they do them well, but there is something awesome about your style. You don't over do it; awesome.

[@ReeWrayOutdoors]

Manny, thank you so much for the kind words. Very sincerely appreciated, sir.

[@lilblackduc7312]

All good tips & tricks! I especially liked that you proved a 24-volt inverter is more efficient than the 12-volt. Thank you...🇺🇸 😎👍☕

[@asedcopf]

I2R loss

[@Doctorfingertips]

This is the good stuff! Well done!

[@ReeWrayOutdoors]

Thank you!

[@autosousao61]

Thanks professor , that's a good thing the i watch this video . I was going to change my battery bank to 24 volts and hook my 12 volt inverter to it ,,,, thanks again.

[@ramfanweber632]

I like your videos, nice setup and quality of your videos 👍🏻

[@ReeWrayOutdoors]

Thanks for the kind words! Very much appreciated. Truly.

[@randallwarren9096]

What I needed to know is 24 volt system to a 12-volt system which one lasts longer on a converter drawing the same amount

[@wrxs1781]

Good video, informative.

[@TexCynRVLife]

Subbed. I watched a few of your vids. You deliver a message well without all the hype! I bought 2 Dr Prepare batteries with the hubs. I went the hub way for now mostly so I could run two 12volt fridges for longer periods of time until the batteries need recharged again. My power stations can't run them for as long. One reason I went this way was so I could potentially consider setting them up for parallel in the future if I find the need for that on solar. For now, I'll use the "KISS" system until my needs change 👍 This video really helps to explain different situations! Thank you!

[@edouardgeyer]

Maybe for many of you ‘hub’s’ is obvious but not for me, so what do you mean by hubs ?

[@TexCynRVLife]

@@edouardgeyer The hubs are the little boxes that click into the power max batteries so you can use USB-C 5V/3A, 9V/3A, 12V/2.5A (Max: 30W) USB-A (1) 5V/3A, 9V/2A, 12V/1.5A (Max: 18W) USB-A (2) 5V/3A, 9V/2A, 12V/1.5A (Max: 18W) DC OUT 12V/10A Cigarette Lighter I use mine to keep 2 12volt car fridges running when I don't have electricity. The fridges can only be ran in ECO mode due to keeping it at low voltage.

[@sunilkumarss6237]

Good presentation

[@johnnymcneill]

To build a system from scratch, starting very small and working upwards, can I parallel smaller charge controllers until I need something larger? Maybe a video showing us newbies how to upgrade would be a good idea.

[@the250mikec]

Super awesome. Thanks

[@ThinkSimply]

THANK YOU for doing the watt hour test with the same device on 12v and 24v. this question has been driving me nuts lol!!!! so its supposed to be the same.... slightly more efficient with the 24v (because the invert runs closer to 95% efficient)

[@stevecharles7967]

Connecting multiple batteries in parallel will ultimately result in one of them failing over time. You replace it, then another one fails no matter how well they are matched. An expensive exercise. To avoid this, use battery isolators that use Schottky diodes that have a low forward volt drop of 0.7V. This ensures that the batteries cannot interact even though they are in parallel.

[@jephtadennison5433]

Do you have a video that can help with this case? Please I will like to see one! Thanks!

[@forester057]

So the power goes out but can’t flow between? Seems like that would cause an imbalance without the flowing between the batteries. They balance with each other just fine (if the wires connecting them are big enough to not limit the current). How is flowing between batteries any different or more harmful that flowing to a power draw. Sounds like an internet old wives tale to me for sure. Batteries fail over time but lithiums last a long time. Longer if you don’t draw down past 20%. Not buying it. The diodes would do more harm than good creating a bigger voltage imbalance if anything.

[@vastirvision]

@@forester057he’s right though. All batteries have unique characteristics, even when specs are properly matched; and these imbalances will only increase over time. Inevitably one of your batteries (let’s say battery X) in a parallel config will drop to a lower voltage than the other(s) (battery Y), and those batteries will in turn begin to send power to that weaker battery. It puts more strain on battery Y, because it is now compensating for the voltage drop in an adjacent batt. You can definitely use batteries in parallel w smart BMS systems that communicate with each other, then you don’t have to worry about this scenario, or you can achieve a stable system by using other components that will keep the batteries actively monitored and balanced. Batteries, in general, operate more comfortably in a series config. There’s no wives involved, it’s EE 101.

[@frankacheampong4490]

NICE PRESENTATION,I WILL LIKE TO TAKE PART IN THE SOLAR GENERATOR WORKSHOP

[@guywood67]

Good Job!

[@loganyoung7051]

solid vid. 10/10

[@user-yr1qw6qb1n]

Hi. Yes the video is informative. Thanks

[@koollee]

Thanks alot. I knew some of but not all of this info. Right now im running 3 deep cycle lead acids parallel And didnt know that its better to have same cable lengths (tho mine arent too far off from each other), and to take positive and negative from opposite end batteries. Its almost 11pm and this video got me pumped up.. almost want to go out in the dark jus to tinker on the batteries lol ... To, as u mentioned, not put more demand on my one battery that has the 2 output terminals connected to it. My idea is to have the solar controller pos n neg on oposite end batteries, then the output on neg and pos that the solar isnt connected to (like an X when all reconnected. Thanks again.

[@pl3637]

Very good video I am wanting to build the most efficient system to run a fridge and a upright freezer still haven’t found a video showing a good system with part lists and step by step instruction on building such system

[@hegefarms4260]

That's what I'm doing looking for info on running a Fridge and Freezer. I'm going with a 24 volt system 4 Li Time 100AH Batteries in series and parallel a Victron 24/ 1200 inverter and 16. 100 watt panels and a Victron 150/45 solar controller. I'm hoping this works

[@winstonsmiths2449]

The length of the individual wires can vary, but the round trip length should be as close to the same length as possible for reasons you mention. It is the round trip or over all length that should be the same. This is easier since you can start with a 10 ft cable for each polarity, cut as needed for each connection. You can have varying lengths due to rack/mounting design. All 10 ft should be used.

[@woodzyfox4735]

Suggestion, Put a red wire on one end of your pairs and the black on the other side, this is help with a more even discharge meaning the leanth wont matter any more

[@olukunleayobamipetrosagboo6164]

Thanks for ur video. Pls can u list all items used .

[@NeoVdV]

What’s the working of the BMS in parallel vs série configuration ? Is it limiting as a single battery.

[@johng.7560]

I chose 24v to keep the wire size down and 24v high ah LiFePO4 batteries are now easier to find.

[@paulgallant8115]

Thank you.

[@grumpyshorts1056]

Do you add discharge amps when you have multiple batteries? Like 2 100a batteries that have a 100a max discharge rate will now have 200a max discharge rate? the higher discharge rate would handle like an RV A/C startup amp draw.

[@aristidesroman435]

Nice video.. And badass battery.. check 20kw power queen battery bank.. STRONG..

[@esiakaharding9124]

well explained

[@tombird306]

Hi. I was wondering about my 24 v trolling motor. I would like to double the run time. Can I run 2 sets on 2 like batteries in parallel and then put them in series? Where would I connect the load pod and neg? What about charging? Thanks for any advice

[@richardthompson5370]

At the very least, it makes sense to install a fuse between batteries connected in parallel. A failure in one battery will place a load on the companion battery and allow excessive current to flow. The result of that could destroy the good battery and produce excessive heat with the very real risk of fire.

[@koollee]

Ohh.. daa-um. Thanks

[@markkingsley7439]

Dude your awesome

[@tomwilliam5118]

Well done

[@brothergeorge3412]

Can you also describe the Battery Cable sizes used in your Videos. Also the Lug 3/8 or 5/16. Thanks great videos

[@todddunn945]

These Chinese batteries all have 8mm bolts. Wire size depends on the maximum power draw of your inverter and the system voltage. For example a 3,000 watt inverter on a 12 V system can draw up to 250 amps (3000 divided by 12). A 250 amp draw will require 4/0 wire. A 24 volt 3,000 watt inverter can draw up to 125 amps, so you will need #1 or #2 wire depending on the temperature rating of the insulation on the wire. Use #1 wire if the insulation is rated to 75C and #2 for 90C rated insulation.

[@rallyraul1]

Loved the video! Great explanation, I now have a much better understanding of how battery banks work. I'm planning on getting solar for my home and was thinking of getting the smallest package available through Tesla without a powerwall and supplementing it with a set up as shown in this video. My average consumption of energy per month is 750 kwh. Any advice for me? your input would be greatly appreciated. Thank you

[@baneverything5580]

See Will Prowse sites, books and vids.

[@conammit]

Should the wires going from the inverter to the batteries be the same length or does it matter?

[@Binkophile]

That's good advice about not mixing up the voltage of chargers. I had one that was switchable between 12V and 24V, but one day I forgot to switch from 24V to 12... Are batteries meant to fizz?😬

[@larryperry2094]

I bet the efficiency difference would have been even greater running fridge or a/c with a induction motor. That would be cool to see. I am planning to make the jump to 24volts soon for the gain in efficiency and to further grow my system.

[@jasonbroom7147]

Not sure if you cover it at some point and I just missed it, but it's crucial that the BMS in the batteries you're connecting in series or parallel are designed to handle that configuration. In particular, if one BMS shuts off and the other battery is pushing all of the current, can the BMS handle that?

[@ReeWrayOutdoors]

Excellent point, Jason. While I did stress the importance of ensuring the batteries are all of the same mfg., age, etc...I definitely wish I'd mentioned that point. These Power Queens specifically indicate they support "up to 4 batteries in series or parallel" for that very reason, I'm sure. I'll post/pin a comment about this, because you're right...it is an important consideration. Thanks for raising the point! :)

[@rustyoc]

I am running 2 x 24v 100ah Lifpo4 in Parallel with an all in one 24v Inverter Solar Charger. When under load one battery drops faster than the other, should they both drop at the same % roughly?

[@user-uz7gu7of1v]

Great video, thank you. Can you discuss a 4 battery, series/parallel(24 volt) arrangement. I am experiencing a "balance" situation with Redodo batteries, and will try a battery equalizer. When one battery discharges more than a half a volt from the rest the BMS stops the battery, and then the equalizer shuts down because there isn't 24 volts anymore. Keep up the good work.

[@andreswart4951]

Good video

[@mfgxl]

When using 12v batteries in series always use a balancer so that the health of the batteries as well as the capacity is not compromised.

[@whochecksthis]

With proper wiring, and cable layout, and Lithium batteries, this is substantially less important than if Lead Acid batteries are used.

[@scottmurphy4946]

People are shocked when they find out I am not a good electrician 😂

[@godfreydebouillon8807]

Great info. Kind of sucks that they all need to be the same age and cycles. That makes it an all or nothing proposition. It'd be nice if you could add batteries as you go, and build it up, and when one goes bad, you simply replace it instead of replacing every one.

[@barrymclaughlin794]

Perhaps I am mistaken but I looked at the comments and I watched the video a few times and it appears that you have connected the output of the Bouge solar controller to the inverter. My understanding is that the output should go directly to the battery bank and then from there to the inverter with the cabling being as close to the same length for all cables and the batteries cabled in a balanced configuration. Please reply or comment if I am mistaken.

[@scomi]

Great video. I'm a newbie at this, but wouldn't the extra efficiency of the 24v test setup have come from using the larger-than-needed cables from the 12v setup?

[@abaanamaan]

Nice video mate what was those tin wire were connected to the batteries I m doing 4x200ah 48v do I need balancer or BMS to keep the batteries under track what you suggested I be using this one solar backup system 8kw inverter

[@mrgraham9007]

When connecting in series, use batteries of same capacity otherwise balance issues can arise, even with lead acid.If the set goes flat, then the polarity of the weakness battery may reverse. I build orr grid systems as a hobby, being a qualified electrical engineer for more than 50yrs. Like your video, great for beginner's.

[@dross24MA]

Wow! I actually understood you on this one! Hahaha!

[@forester057]

Another old school wives tale left over from lead acid battery tech. Lithium can match voltage among batteries very quickly limited only by wire gauge. There are plenty of tests showing how a power draw pulls more from the bigger battery in the parallel system. There is no imbalance except what is created by wires sized too small. You’re right if you’re talking Lead acid, but they suck so who cares about those dinosaurs when lithium is so cheap now and outperforms and outlasts hands down.

[@swkaushik]

Great Sir

[@bobnunamamn2228]

Great video once more I just bought the 3 pack of these Power Queens on sale for $750, can I use just the three in series I want to power my Pecron E 2000 at night or on cloudy days or do you recommend the 4th so I can run a 24 volt parallel, 2nd question for my output from the batteries (8AWG) can I just run them into an MC4 to hook into my aviation plug? Thanks in advance and also for inspiring me to get partially off-grid :)

[@Digidoc316]

Very simple; hybrid. Series adds voltage but not current, parallel adds current but not voltage. build in series to match your inverter, then tie the series strings together to get the desired current.

[@woodzyfox4735]

They get charged up to 14.5V for max cap with out over charging. but you CAN go to 14.8V. i do mine to 14.5 to be safe I have the WEISE version of them batterys (best for the money). Max low is 11.0V Max high is 14.8V 1C rateing (100A dis/recharging). I discharge mine to 11.5V and charge max 14.5V

[@emmanueloluwole764]

Please can you also give a teaching on how to use a meter

[@mgentile7]

is there a tutorial of the entire set up? Including the solar control, breakers, etc....

[@TheHuntrees007]

Hot dog! I've just found my solar teacher!

[@RealSteel319]

So I'm wanting to run a 700w microwave and a TV and a game system part time and my 12v refrigerator freezer all the time I have 300 watts of solar and two 100 amp hour batteries, after only watching half of your video I'm pretty sure I need to go parallel because I'm way below 3000-watt ?

[@tw7165]

I have 2 12v batteries in series. I have a double bank 12 V charger. Do I need to use both banks to charge both batteries? Any harm in charging both batteries with both banks?

[@johnemmons9087]

Hi. Great video! I have stumbled on a problem. I have 8 - 12v marine batteries for my solar panels. I also added a ProMariner battery charger for backup. I have the charger (advice from a boatyard) wired in series and when it charges, the front two batteries get really hot. Looked online and discovered the batteries need to be balanced charged. Do you think the bus bar idea you had would work? And how would that effect how to wire them into the RVs system. Thanx!

[@todddunn945]

When you are building a large parallel bank you should wire the individual batteries to bus bars, not directly to each other. Just make sure all the wires are the same gauge and length. The connect your load and charger to the bus bars. That way of wiring your system will solve your problem.

[@johnemmons9087]

Thank you! God bless you!

[@christopheranderson8275]

To get the most longevity out of your inverter you should mount it so the fans are blowing up. This works with the natural ability of heat rising and will lower the operating temperature of the inverter making it last the longest time possible before failure. Great informative video!

[@matino717]

My issue is quite unique I think... I was importer of electric unicycles and have about 20 to 30k wh battery packs which I wanna use to make my RV battery system, but they almost all are 67V... now I'm wondering If I should dismantle all cells of if packs could be used as is to avoid massive work...? What's your opinion on that?

[@kiranks1984]

Nice video for beginners...Do the inverters not charge the battery? Why a seperate charger?

[@ReeWrayOutdoors]

You can buy an "inverter/charger" hybrid all-in-one unit - but in this example, I'm showing a modular system. But typically, if you're just buying an AC inverter - it usually will not have a solar charge controller capability, unless you're specifically buying an all-in-one hybrid unit that has: AC charging, Solar charging, and AC inverter all neatly packaged in one wall-mountable enclosure.

[@richarddaugherty8583]

Excellent presentation! I noticed that you didn't use any fusing between the battery bank and the inverter. Was that to keep it simple for the presentation, or is it just unnecessary? I built a 400 amp hour solar generator in the first year of the pandemic. I used both a fuse and circuit breakers between the battery bank, and between the solar input (no fuse there) to the charger and the leads from the panels. As I'm a ham radio operator and this is for my mobile radio station, I went parallel as all my radios and appliances are 12 volt and I didn't want to lose power in the conversion. Love LiFePo4 batteries! Lithium Ion and polymer scare the heck out of me.

[@ReeWrayOutdoors]

In that particular setup, I was using a breaker in place of a fuse, just because it was easier to disconnect/reconnect. As long as you're using a good quality reliable breaker, that's really sufficient. But sufficient isn't always optimal. Now i actually have a fuse in-line off the main positive battery terminal...and connect that to a disconnect switch. That actually provides better protection to the cable since the fuse will experience the high current first. But yeah, you definitely need a good breaker or a fuse between the battery and the load, no matter what.

[@user-kr7ck9lc6s]

What size AWG cable did you use between the 2 batteries as jumpers? Is it the same as the cables feeding the invertor (1/0 perhaps?)

[@mileshanley8052]

Question. I will be building a 24v system for an equipment/tool shed. For simplicity I was going to use a single 24v 100 AH battery. Should I consider using 2-100 AH 12v batteries wired in series or stick with the single battery?

[@TacticalGhost007]

Always use a 24v battery rather than 2x 12v when you can find them at the right price to avoid balancing and batt failure issues. Also look at purchasing 200aH, 300aH or even 400aH batteries in lieu of 100aH.

[@noahriding5780]

When you have a voltage max cap problem start up in a battery, how do you tell fixable wear from permanent damage on a battery? Thanks.

[@Desertphile]

The maximum number of batteries connected depends upon what the manufacturers say. Usually this is 4S4P, with battery balancers and parallel chargers. Also, if someone follows your advice, they should get Bluetooth batteries so that they can monitor what each battery is doing.

[@SuperVstech]

Most LFP 12V battery manufacturers only allow 4s OR 4p none I have seen allow both.

[@PersonalStash420]

@@SuperVstech not true.

[@SuperVstech]

@@PersonalStash420 i stand corrected.

[@Dave-xr9bc]

a very instructive video. what i still want to know is can you charge them in parallel with a solar panel or do you have to charge them separately?

[@ReeWrayOutdoors]

You still need a charge controller, obviously, but yeah, you can charge them together in parallel.

[@DIY12-24v]

17:17 you forgot a very important device. When lithium is in series you need to have a battery balancer or your batteries SOC will drift apart

[@Gawieseplaas]

Thanks for the video. When one opts for a lead acid battery should one increase the battery capacity to compensate for the shallow (50%) discharge threshold?

[@ReeWrayOutdoors]

For the purpose of calculating usable capacity, absolutely.

[@occamraiser]

I wouldn't dream of using big LiPo batteries any more than I would dream of storing explosives. Both are perfectly safe until something goes wrong, and you won't be around to solve the problem if it goes wrong since the point of solar systems is that they run unattended. I'll stick to lead acid thanks.

[@seymourpro6097]

My simple theory about battery voltages is; If you have a need for DC power then use that voltage, beware of high currents! If you have a need for mains voltage then pick a high battery voltage for efficiency (no-one uses solar if they have unlimited mains!) At low volts the current must be high to make power which demands big wires and fat lugs and risks hot wire and hot connections -which are both inefficient uses of the stored power.

[@techkidstronics6998]

I have 9 100Amp lifepo4 batteries and I want to make 24v battery pack. So is it possible to keep 2 batteries in parallel and others in series? What is the amp I can get? I am using jk bms as battery balancer and 24v inverter.