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BYD BMS

Right above your comment.
So far, I am comfortable using the charger/inverter to set the charge voltage limits, and this balancer, with no "BMS".

I keep my batteries inside, so I am not concerned with temp limits that a BMS provides. I would suggest the Chargery BMS is probably as good as a BMS gets, along with this less powerful balancer than the 1S balancer.
 
I consider a balancer to be a type of BMS since it is actively managing the battery. Maybe that's an error in terminology on my part.
 
I consider a balancer to be a type of BMS since it is actively managing the battery. Maybe that's an error in terminology on my part.
The ANT BMS has far more features that you can "dick" with. I would put forth, they are irrelevant and cause more confusion than they are worth.

The critical voltage of the battery level can be managed with the charger, the top end, and the bottom end. The balancer in my view is much more important than any other feature a BMS provides.

In the case of used cells/packs, such as these BYD's there is usually one often two cells that are degraded. Anywhere from 60% to 80% of the capacity is lost due to imbalanced cells. Just keeping the low cells in balance will keep the average voltage of the pack up, and thus keep the battery in operation.
 
OK, Nevermind the 1S BMS's.

I just got these 2 amp BMS's.

I have been using the 1A version for about 6 months and I am satisfied. Not a BMS but a pretty good active balancer that is active all the time and not just the top and bottom end.
It is generally marketed as jkbms.
I paid $86 for 1A version on eBay.
Much better than the $35 dumb active balancer that would only work on bottom or top and tiny current balance.
 
Two amp balancer installed and operating.

Pretty easy replacement. just cut off BMS lines one at a time then crimp on the new balancer harness.

I m going to see what happens on the second set with both the BMS and Balancer connected. I like the BMS with its screen display. Not exactly necessary with the Bluetooth app. But it's always nice to just look at the thing and see what it is, instead of getting the phone out.

Setting to 2.0 amp balance and the balancer won't balance because of too much resistance!

This won't be a problem if I put the lines on the cells directly. This is considerably more work since all the packs are on the rack and you have to take the shell off to get to the cells. ?

And the app won't let me change the name of the device. Kind of a problem when I have four on the same system. tHe ApP wOnT lEt Me ChAnGe ThE nAmE oN tHe PhOnE bUt WiLl On ThE TaBlEt. ?‍♂️
 

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If you paralleled your cells within each pack, pack to pack - as DavePoz did, I think you can get by with one balancer. You will have to take the plastic shell off so you can put the balance wires directly to the cells. The internal tracing thingy has too much resistance. Unfortunately, this pretty much makes the entire point of "Plug and Play" moot, which is the point of this entire thread.

As I watch the balancer balance, it's neat to see the low V dud keep getting current from the high V cell. It's the middle of the day, and I am running my entire house off the packs now, it's also a cloudy day, so not much recharge happening from the solar.
 
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Also found this which has more options.

US $11.85 23%OFF | 1A 2A 5A 10A Balance Lithium Battery Active Equalizer Bluetooth 2S ~ 24S BMS Li-ion Lifepo4 LTO JK Balancer Protection Board 4S
 
Hello together,

first, my name is Stephan from Germany and my English might not be perfect....I found this threat maybe fits to my aim.
I´m going to build a powerwall 48V 200Ah cells for my house.
Problem is in Europe to find an solar inverter to work with "open, free" battery configuration. Manufacturers of solar inverters state that their devices will only work with an BYD pack, eg.. But commercial battery packs like LG or BYD are extremely expensive and not economic (maybe an LG pack with 10KWh cost about 6000€, almost 7000$).
So I bought that CARB cells LiFePO from Aliexpress and wanna build a battery pack with a BMS that will be noticed as BYD-battery pack from the inverter to work with it.
Shown in the first video from @@jasonhc73 a standalone pack with BMS is no problem, but communication with the inverter I don´t know how to manage. The aim is to simulate a BYD battery pack for the inverters communication.

Does anybody know ho to manage?

Stephan
 
Hello together,

first, my name is Stephan from Germany and my English might not be perfect....I found this threat maybe fits to my aim.
I´m going to build a powerwall 48V 200Ah cells for my house.
Problem is in Europe to find an solar inverter to work with "open, free" battery configuration. Manufacturers of solar inverters state that their devices will only work with an BYD pack, eg.. But commercial battery packs like LG or BYD are extremely expensive and not economic (maybe an LG pack with 10KWh cost about 6000€, almost 7000$).
So I bought that CARB cells LiFePO from Aliexpress and wanna build a battery pack with a BMS that will be noticed as BYD-battery pack from the inverter to work with it.
Shown in the first video from @@jasonhc73 a standalone pack with BMS is no problem, but communication with the inverter I don´t know how to manage. The aim is to simulate a BYD battery pack for the inverters communication.

Does anybody know ho to manage?

Stephan
First you need to post what inverters your considering. Most inverters I've seen don't limit the battery used. The chemistry of battery is generally the limitation. Just because a retailer who is trying to sell you a high dollar battery doesn't mean that's truly the case. It's not usually profitable for inverter manufactures to only support one battery manufacture.

I think more information is needed for anyone to help you.
 
Yes, maybe SMA SunnyIsland, Victron Energy Multiplus 2-GX or Solis RHI-3.6K-48ES-5G.

I don´t know all possible good 48V hybriid inverters.
I believe David Poz setup his workshop with sunny island and 48v BYD battery setup.
You may check his youtube.
 
I found a video disassembling an old 48V battery pack and adding a BMS...but no connection to the solar inverter...
 
SMA Offgrid
MPP-SOLAR
Growatt

Look at 2nd teir no name brands.

Even midnight solar, outback solar all work without bms controller connections.
 
I found a video disassembling an old 48V battery pack and adding a BMS...but no connection to the solar inverter...
I have MPP-Solar LV5048 hybrid inverter like a lot of people here with BYD batteries.
Wiring is pretty simple with the hybrid inverter setup.
It is basically AC-in, PV in, battery-in, power-out.
I seem to like the growatt specs too.
It all depends on how you want to connect/offset your use. Grid-tie or off-grid.
 
Hello,

therefore my solarplant will be sized approx. 8,4 KWP zhe only economic way is to build a on-grid system.
In Germany you´ll get some Euro-Cent/KWh...feeding the grid

Additional complicating is that only certified and tested inverters will be allowed to install.
 
Hello,

therefore my solarplant will be sized approx. 8,4 KWP zhe only economic way is to build a on-grid system.
In Germany you´ll get some Euro-Cent/KWh...feeding the grid

Additional complicating is that only certified and tested inverters will be allowed to install.
Your likely going to have issues here as most diy builds don't meet electric company requirements. Why are you getting batteries for a grid tie system? Micro-inverters or hybrid inverters are generally used for this purpose.

I would look at installing micro-inverters and having a smaller off grid system for dedicated outlets. Or backfeed the micro-inverters with a pure sine wave inverter.
 
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