JK BMS Install and Configuration

[@StuartCarlisle-tc3wx]

Spell check is driving me crazier than I am already. Ratios came from the ether. Not me. And thanks again for doing what you do.

[@johnnylightning1491]

Thanks Clark, pretty informative video. Now I know why bluetooth is so valuable in a battery. Keep the good stuff coming.

[@StuartCarlisle-tc3wx]

XY Digital Co. LTD is who is selling through Walmart. From what I can see it is returnable through Walmart.

[@elmer665544]

You don’t want the balance to start at 3.02v. That’s too low and will try to balance in the flat part of the curve. It needs to be set at 3.40v-3.45v to top balance.

[@Clarks-Adventure]

Sure, whatever you like

[@elmer665544]

@@Clarks-AdventureI see later in the video it is set to 3.29. Probably should be a little higher than that but neither will hurt anything.

[@SkypowerwithKarl]

Elmer is correct. You don’t want it to balance that low, it could cause great difficulty balancing at full charge, especially if the battery spends a few days balancing in the flat of the curve. After a couple years of using JK’s I’ve found some happy numbers. This is assuming that the Bulk/absorb is set to 3.45 volts per cell (13.8 four cell ) Start balance voltage, Eve cells 3.41 and CATL 3.42 volts. If charger gives you the ability to adjust tail current or absorb time instead of a fixed algorithm, you could even raise the start balance a bit higher (closer to the bulk voltage). Regardless, not below 3.4 volts per cell.

[@StuartCarlisle-tc3wx]

Using your description for ratios BMS (JK BMS 4S 5S 6S 7S 8S 200A Smart BMS Smart BMS Built-in Bluetooth APP Support LCD 12V 24V 3S (D), will that be the same? I found it on another source.

[@Clarks-Adventure]

If your source was on Amazon send me a link to [e-mail] I'll check it and maybe use it

[@wimclinckspoor5731]

Hi, i have several jkbms’s installed and my experience is that the set voltage to start balancing is around 3.45 V for LFP cells.

[@Clarks-Adventure]

Thanks, that seems to be the consensus

[@westmc45]

So do is a BMS needed for each battery or can the BMS control 4 batteries that are in parallel

[@Clarks-Adventure]

If the cells are in parallel -one BMS If the batteries are in parallel - multiple BMSs

[@leandroflaherty]

Single point of failure even if it was possible..

[@dc1544]

I prefer .005 volts for balance trigger. Starting the balance at that low means it will keep your cells unbalanced. you want it to balance when first cell hits max cell voltage that you set. usually its 3.45 volts (13.8 total volts). Trust me on this I spent 12 months out of balance then switched mine starting to low like 3.1 but doing higher like 3.45they balanced within a month. Remember these are big cells and you want all to hit 3.45 at same time. LFP BMS setting for balance has been tested and confirmed by me and many others like OFF Grid Garage. You will see if you use this battery all the time. I can explain more if needed.

[@Clarks-Adventure]

I understand. Good idea. With this specific set of well balanced cells I think there is no wrong answer. But listen to his advice.

[@uhjyuff2095]

Your settings are spot on for "Top balancing" a lifepo4 battery pack. My pack has a cell that has less capacity than the rest and also my solar charge controller is not designed for lithium. If my bms shuts off discharge from a low cell the charge controller goes to sleep and never comes back on. My solution was to bottom balance the pack and my charge controller will shut off the load at low pack voltage every time without a cell dropping too low. This is the first battery I have ever had a need for bottom balancing but its working like this for many months flawlessly.

[@dc1544]

@@uhjyuff2095 Yes why don't you replace the cell. I never top charged my cells before I built them. I had huge differences till I figured out how to get all my settings right. My inverters stop charging for 90 minutes after the BMS's stop taking a charge. they still cover loads with PV power after they use all the stored power. In spring summer and fall I turn down my inverters charging to 18 amps each. With the amount of sun hours I fill up every day easily unless its rainy ten next day it fill up. My central air runs day and night now so I use around 25kw a day and winter its 15kw. I like to keep it close with how many amps I use to charge. no reason to over work my system when I have 52kw usable battery banks. I see the new cells for $70 that have 330ah per from china now. I paid $115 for 280 lfp cells each. My cells average around 178ah. Might be time to add another bank.

[@Clarks-Adventure]

I have a similar issue with knee cell in my Redodo 410. The BankManager has a feature that disconnects this bank once it's at a certain POC. Works for me and I can stay with top balancing. Charging to 100 means no cell memory.

[@uhjyuff2095]

@@dc1544 I think my issue is the charge controller is not built for lithium packs that have a bms. When the bms shuts down my charge controller will not turn back on even if solar is connected and the sun is shinning.

[@bitsurfr46]

This sounds like something I wouldn't like to do myself. I would find it difficult to find anyone to do something like this in Saint Augustine.😢

[@brownnoise357]

Hi Clark. Great videos on BMS. 👍 Clark something has cropped up that I’m not in a position to check at the moment, but if it’s correct, it means that I am sticking only with AGM Batteries on my next Sailboat, until I can chat with the insurance company or Companies. I have heard that if you have lithium batteries on your boat, and it catches fire, then your insurance cover is nullified? If this happens in a Marina, the nightmare scenario is horrific, and from what I have heard, every single insurance company now has this get out clause. So for me, until this is sorted out, I’m sticking with just AGM and can add Lifepoo4 bank once cover is certain. So how is the situation with your insurance company cover, I suppose is the question ? Best Wishes. Bob.🤔🌟🌟🌟⛵️❤️

[@Clarks-Adventure]

I don't insure out here.

[@brownnoise357]

@@Clarks-Adventure Oh that’s interesting to know. Thanks Clark. At least initially, it looks like I can’t avoid insurance to start with, so starting AGM only won’t hurt for a while, and I can concentrate on getting Solar and Wind sorted, to keep the AGM’s happy, then add the Lifepo4 Bank(s) later. All the Best. Bob. 🤔🌟🌟🌟👍❤️🏴󠁧󠁢󠁷󠁬󠁳󠁿🇬🇧

[@Clarks-Adventure]

In the states I go liability only. www.skisafe.com/ They have never asked about batteries. They don't even require a survey

[@brownnoise357]

@@Clarks-Adventure I went similar with my last Sailboat in the USA in 2016, and after losing my boat after the attack in New York Harbour I lost everything when they failed to pay me out for the third party expenses. I’ve been Boatless and landlocked ever since. Still, there’s light at the end of the tunnel at last my Silver investment I made years before, looks about to pay off. Bob.👍🌟🌟🌟🙂⛵️❤️

[@dracey1778]

Way more interesting than I thought it was going to be.

[@Clarks-Adventure]

Thank you

[@OnerousEthic]

Finally the rubber meets the road!

[@goodq]

Hi Clark. The BMS once you changed the cell count from 8 to 4. It seems to have reverted back to eight not sure if you noticed that. See 2:51 4:20 you mentioned trying to target 13.1 for balancing. I think the setting for that will be 3.275 rather than 3.02. Absolutely lovely video learned the whole lot. Thank you very much as always.❤

[@Clarks-Adventure]

Yeah I didn't hit the ok button when I entered 4 cells. It all worked in the end

[@goodq]

How cooool!!! thanks Clark

[@ColinWetherelt]

Hello there, Clark. I want some of your knowledge. Do you do consulting?

[@ColinWetherelt]

I just ripped out all the ancient electronics in my A30 sailboat I'm refitting.

[@Clarks-Adventure]

Yes our Dream Believers tier on Patreon has become a defacto consulting service. Sign up there and we will talk about what you want to do on the phone.