Mixing "brand" lithium batteries

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Gtx Gaming

Gtx Gaming
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Hi Forum members

I Currently have the growatt 5000 ES Inverter and freedom won tower e5000 battery. With bms cable connected to it. 8x 575watt longi panels.

I Want add more battery storage, but the freedom won batteries about 18k each. I was thinking adding 2x these

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
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Should I risk it? I Don't think I will be able connect to bms, them as they different brand?
So I might need run them as dummies and no bms cable going to them?

They should keep in sync all same voltage?
 
Terrible idea long term to forego BMS to save a few bucks.

Also could mean you have little to no warranty cover.

But the link doesn’t work.
 
You can't. Different BMS's. You can't even mix different sizes of the same brand, unless their BMS specifically allows it.

As @SauRoNZA said you will probably void your warranty on the batteries by running it with no BMS...
 
Also quite a bit cheaper here…

thepowerstore.co.za

Freedom Won E-Tower LiFePO4 Battery 5kW 52V

Freedom Won E-Tower LiFePO4 Battery 5kW 52V The Freedom Won eTower 5kW , 52V battery The Freedom Won eTower is an economical and modular Life PO4 Solution for residential and light commercial applications Product Features 5kWh battery with a 90% DoD Parallelable up to 15 Units Stackable up to...
thepowerstore.co.za thepowerstore.co.za
 
SauRoNZA said:
Also quite a bit cheaper here…

thepowerstore.co.za

Freedom Won E-Tower LiFePO4 Battery 5kW 52V

Freedom Won E-Tower LiFePO4 Battery 5kW 52V The Freedom Won eTower 5kW , 52V battery The Freedom Won eTower is an economical and modular Life PO4 Solution for residential and light commercial applications Product Features 5kWh battery with a 90% DoD Parallelable up to 15 Units Stackable up to...
thepowerstore.co.za thepowerstore.co.za
Click to expand...
Nice il grab it from them
 
Gtx Gaming said:
Hi Forum members

I Currently have the growatt 5000 ES Inverter and freedom won tower e5000 battery. With bms cable connected to it. 8x 575watt longi panels.

I Want add more battery storage, but the freedom won batteries about 18k each. I was thinking adding 2x these

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com

Should I risk it? I Don't think I will be able connect to bms, them as they different brand?
So I might need run them as dummies and no bms cable going to them?

They should keep in sync all same voltage?
Click to expand...
product gone? link not working or just me?

nvm....
 
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Gtx Gaming said:
Hi Forum members

I Currently have the growatt 5000 ES Inverter and freedom won tower e5000 battery. With bms cable connected to it. 8x 575watt longi panels.

I Want add more battery storage, but the freedom won batteries about 18k each. I was thinking adding 2x these

Takealot.com: Online Shopping | SA's leading online store

South Africa's leading online store. Fast, reliable delivery to your door. Many ways to pay. Shop anything you can imagine: TVs, laptops, cellphones, kitchen appliances, toys, books, beauty & more. Shop the mobile app anytime, anywhere.
www.takealot.com www.takealot.com

Should I risk it? I Don't think I will be able connect to bms, them as they different brand?
So I might need run them as dummies and no bms cable going to them?

They should keep in sync all same voltage?
Click to expand...
You WILL void your warranty mixing brands rather save up and buy another etower later on when you can afford it. And mixing different brands might shorten the battery life because of the different voltage settings they have
 
If you have Lifepo4 batteries with the same number of series cells, they can be run in parallel - the internal BMS's will control the charging, discharging and cell protection. The inverter just needs to be set to the correct charging voltage, and both batteries run un-comm'd.

The main risk would be should if a BMS should fail on one battery, and create a current sink for the other. So each should be fused to prevent that. And you'd like the batteries to be at the same voltage level when connecting up initially...

Have a chat on powerforum.co.za - lots of clued up folks there.

And yes, I'd imagine warranties will be up for discussion if something fails - even though there's nothing fundamentally preventing this implementation.
 
igeorge said:
If you have Lifepo4 batteries with the same number of series cells, they can be run in parallel - the internal BMS's will control the charging, discharging and cell protection. The inverter just needs to be set to the correct charging voltage, and both batteries run un-comm'd.

The main risk would be should if a BMS should fail on one battery, and create a current sink for the other. So each should be fused to prevent that. And you'd like the batteries to be at the same voltage level when connecting up initially...

Have a chat on powerforum.co.za - lots of clued up folks there.

And yes, I'd imagine warranties will be up for discussion if something fails - even though there's nothing fundamentally preventing this implementation.
Click to expand...
The amount of top of the range batteries manufactures that just deny warranties and blame inverters or other thing that customers have no control over.
 
Saw a house in Darling, that was using a 5kW of unknown Chinese make and a 10kW Volta battery with an Axpert 5kW inverter. Connected in parallel

It had been working like this for at least 4 years without any apparent problem

Both batteries SOC light showed 75%
 
chrisc said:
Saw a house in Darling, that was using a 5kW of unknown Chinese make and a 10kW Volta battery with an Axpert 5kW inverter. Connected in parallel

It had been working like this for at least 4 years without any apparent problem

Both batteries SOC light showed 75%
Click to expand...
Damn thats impressive to mix 5kw and 10kw, wonder if should take risk.

I dont even know how claim warranty if my battery does fail, as it just came as part of the house. Has 2022 sticker on it.
 
Gtx Gaming said:
Damn thats impressive to mix 5kw and 10kw, wonder if should take risk.

I dont even know how claim warranty if my battery does fail, as it just came as part of the house. Has 2022 sticker on it.
Click to expand...
I would spend the extra on the FW they are good quality.
 
The sizes don't matter - the voltages just need to be the same, and the battery chemistry. Given the way the Chinese are driving down the cost of LIFEPO4 batteries, it makes mixing and matching very attractive. Esp if you're trying to find another 5yr old model from a known brand - it's going to be so much more per kWh.
 
SauRoNZA said:
Terrible idea long term to forego BMS to save a few bucks.

Also could mean you have little to no warranty cover.

But the link doesn’t work.
Click to expand...
All batteries have a bms going without coms is not a problem

No coms does not equal no bms
 
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Coms is overated
Especially if your bank is big enough to run overnight without dipping under 20%soc

Yes you can mix different brands and capacities ie 5kwh and 10kwh no problem

Like others have said as long as you match the voltage

So if you have 15S 48v batteries all must be 48v

Or 16S 51.2v all 51.2v

Have 2 batteries running like this 1 has coms the other runs as dumb/self managed unit

the built it bms protects it from going oug of range

It just suppliies half the power and takes half the charge current

Parralel self balances
Really not a big deal
 
You can mix batteries of different sizes as long as ALL the following are true:

They are the exact same chemistry and cell number (no you cannot mix a LiFePO4 with a NMC)

Each battery has its own bms that balances (cheap ones don't self balance. It is a braai waiting to happen. You don't need coms)

Each battery has its own physical fuse

You have reasonably thick cables to do the parallel connections (good bet is same gauge as the wires coming to/from the inverter)
 
agentrfr said:
You can mix batteries of different sizes as long as ALL the following are true:

They are the exact same chemistry and cell number (no you cannot mix a LiFePO4 with a NMC)

Each battery has its own bms that balances (cheap ones don't self balance. It is a braai waiting to happen. You don't need coms)

Each battery has its own physical fuse

You have reasonably thick cables to do the parallel connections (good bet is same gauge as the wires coming to/from the inverter)
Click to expand...
You could parralel lifepo4 and nmc

ie if you use a 13s nmc and a 15s lifepo4 and use voltage range that works for both

The worst that can happen

LIfepo4 will do more of the work in the upper voltage range

And the nmc more of the work in the lower voltage

The reason you would not want to do this is that you would run the one battery below the 20% more regular than others

If the bank is big enough that you never let this happen you could happily mix nmc and LIfepo4

Some Marine users do exactly this though they mix lead and lithium
So radios etc can still function in lithium trip scenarios and for cranking amps
 
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