Mixing "brand" lithium batteries

bhaziwa said:
If the voltage of the batteries are the same like 48 to 48 or 52 to 52. They should work just fine. Current is how much electricity a battery holds. Moreover, the only problem you could face is when the batteries have different discharge, a 1c of 10kwh won't draw the same as 1c of 5kwh better have a 5kwh of 1.5c in depth of discharge to parallel with 10kwh. Maybe babbling. I don't mind being corrected.
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The 10kW will supply twice the current as the 5kW keeping voltage the same.
 
I went back to the house in Darling today where the owner has a 10kW and a 5kW battery in parallel

Connected a Raspberry Pi and Solar Assistant. Wirh the inverter supplying 550 - 600 watts, each battery measured individually supplied 605 - 650 watts. I let each battery run for about 90 mins.

The SOC of the 10kW battery measured 91% and the 5kW measured 89%

The 10kW battery has done 1991 cycles and the 5kW has done 1945 cycles

I did not experiment connecting the BMS together as the Chinese battery just states "Compatible BMS"
 
chrisc said:
I went back to the house in Darling today where the owner has a 10kW and a 5kW battery in parallel

Connected a Raspberry Pi and Solar Assistant. Wirh the inverter supplying 550 - 600 watts, each battery measured individually supplied 605 - 650 watts. I let each battery run for about 90 mins.

The SOC of the 10kW battery measured 91% and the 5kW measured 89%

The 10kW battery has done 1991 cycles and the 5kW has done 1945 cycles

I did not experiment connecting the BMS together as the Chinese battery just states "Compatible BMS"
Click to expand...
So seems pretty much in sync and just worked?
 
chrisc said:
I went back to the house in Darling today where the owner has a 10kW and a 5kW battery in parallel

Connected a Raspberry Pi and Solar Assistant. Wirh the inverter supplying 550 - 600 watts, each battery measured individually supplied 605 - 650 watts. I let each battery run for about 90 mins.

The SOC of the 10kW battery measured 91% and the 5kW measured 89%

The 10kW battery has done 1991 cycles and the 5kW has done 1945 cycles

I did not experiment connecting the BMS together as the Chinese battery just states "Compatible BMS"
Click to expand...
That doesn't make sense. 2 batteries supplying 650 watts equals 1300W. SOC calculations are very bad with LFP batteries due to flat voltage curve. The bigger battery will always take more of the load.
 
chrisc said:
I went back to the house in Darling today where the owner has a 10kW and a 5kW battery in parallel

Connected a Raspberry Pi and Solar Assistant. Wirh the inverter supplying 550 - 600 watts, each battery measured individually supplied 605 - 650 watts. I let each battery run for about 90 mins.

The SOC of the 10kW battery measured 91% and the 5kW measured 89%

The 10kW battery has done 1991 cycles and the 5kW has done 1945 cycles

I did not experiment connecting the BMS together as the Chinese battery just states "Compatible BMS"
Click to expand...

Would be interesting to see at higher loads. I expect the 5kwh's SOC would be a few percentages lower then.
Long periods of high load is where there may be some issues but the BMS on the 5kwh should kick in to protect it if it gets into that situation.
 
B-1 said:
You would have to buy enough to make the shipping worth while by buying more than one battery or doing a group buy.
Shipping by boat is about 1000usd if you split that with 2 or 3 other people its not such a big amount anymore.
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Lest we forget the last deal to make shipping cheaper…and people losing their money.
 
wingnut771 said:
That doesn't make sense. 2 batteries supplying 650 watts equals 1300W. SOC calculations are very bad with LFP batteries due to flat voltage curve. The bigger battery will always take more of the load.
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I think you mis-read or I did not explain properly. I connected the batteries one at a time to see how they fared
 
chrisc said:
I think you mis-read or I did not explain properly. I connected the batteries one at a time to see how they fared
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Ah. Thought the whole agenda was how both batteries of different sizes team together and share the load.
 
bhaziwa said:
If the voltage of the batteries are the same like 48 to 48 or 52 to 52. They should work just fine. Current is how much electricity a battery holds. Moreover, the only problem you could face is when the batteries have different discharge, a 1c of 10kwh won't draw the same as 1c of 5kwh better have a 5kwh of 1.5c in depth of discharge to parallel with 10kwh. Maybe babbling. I don't mind being corrected.
Click to expand...
Depends what your aim is

The C you deaw per battery drops so the more batteries the lighter each battery is working

Sure it is a good idea to buy batteries that can meet the max draw of the imverter so if a battery fails you can carry on as per normal with whatever battery is left

But you don't have to if you know what you are doing and can adjust usage to match
 
SauRoNZA said:
Lest we forget the last deal to make shipping cheaper…and people losing their money.
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Yea the problem is you need know you have a reputable supplier

If you can get a big enough order to buy from EVE direct the producer then that headache dissapears

That opens up another headache
Once the order is big enough you wake up NRCS and Customs (more than 3 orders per year or total exceeding R20K)

Customs is easy if already registered as importer

NRCS it would help if somone bumped their head already and know what stupid response you got and what stupid hoop you had to jump through - small orders you can claim sample ordeer big not so much

And with government already making clear they want tk throw rocks in the road for solar and batteries

This can be a painfull exparience or not who knows government agencies certainly doesn't know their arse from their elbow
 
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SauRoNZA said:
There is a whole massive thread for that.

Scott’s Shipping “Liquidation”.
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Thanks, but 99 pages....

tldr.
1747736795859.png

My 2 x 12V 100Ah are still performing like new, eagerly waiting at 100% SOC on float for months on end waiting for that power failure.
 
wingnut771 said:
Thanks, but 99 pages....

tldr.
View attachment 1821695

My 2 x 12V 100Ah are still performing like new, eagerly waiting at 100% SOC on float for months on end waiting for that power failure.
Click to expand...

Yeah but basically plenty of people got on the “buy in bulk, ship it together for cheap” wagon and never got their goods.

That’s besides the dodgy product and repair/warranty issues.

People more often than not forget that what you pay for with the big brands is the ongoing support, especially for things with 5-10 year warranties.
 
SauRoNZA said:
Yeah but basically plenty of people got on the “buy in bulk, ship it together for cheap” wagon and never got their goods.

That’s besides the dodgy product and repair/warranty issues.

People more often than not forget that what you pay for with the big brands is the ongoing support, especially for things with 5-10 year warranties.
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I can't wait for my batteries to break so I can cut them open and see what we're working with.
 
Looks like im going try mixing, i saw takealot finally resolved one my issues and credited me, so decided to use ther credit before they change there mind. Grabbed the following battery Dyness 51.2V 5.12kWh Lithium Battery BX51100.

It was basically free, I have written off this money last year lol
 
Gtx Gaming said:
Looks like im going try mixing, i saw takealot finally resolved one my issues and credited me, so decided to use ther credit before they change there mind. Grabbed the following battery Dyness 51.2V 5.12kWh Lithium Battery BX51100.

It was basically free, I have written off this money last year lol
Click to expand...
as long as the other battery is also 51.2V.
 
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