Re: Looking for turn-key BMS system

On 03-10-2024 11:17, Klaus Vestergaard Kragelund wrote:

On 03-10-2024 00:31, Lasse Langwadt wrote:

On 10/2/24 15:12, Klaus Vestergaard Kragelund wrote:

Hi
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One of my clients is looking for replacing existing HW, 2 200Wh battery modules, which each has a BMS controller, that monitors and balances 12 lithium ion cells (4 series connection of 3 parallel cells). Each of the modules has SOC output in the form of LEDs.
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Beyond that, the overall system has a BMS controller that is powered from either 24VDC (grid connected) or from the batteries. This BMS controller also has SOC, with a connected display.
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The client would like a turn-key solution, so minimal NRE due to low volume.
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I am looking for a supplier of finished batteries with BMS and also BMS controller. Perhaps one of you guys has worked with this? (need a stable supplier)
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Client is based in the EU.
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Thanks
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Klaus

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https://www.victron.dk/ ?

 Looks good, they have a lithium battery with internal BMS at resonable price.
 No State of Charge (SoC) though for the battery. Is it possible to get rough SoC from a lithium battery by voltage sensing only?

A number of hits online says that SoC is difficult to determine for a Lithium battery purely from the voltage.
But for the cell I am using, the datasheet seems to disagree (if compensated for temperature)
https://electronicsdesign.dk/tmp/ur18650.pdf