Newbie, diy powerwall

[Mechsman]

Hi All,

I'm new here, so apologies if this is in the wrong place. I am currently in the process of collecting bits to build a DIY powerwall and I was hoping for some advice as the voltages etc are similar to low power ev's.

The inverter I have runs 4 cartridges of lead acid gel batteries. Each pack is 96v nominal and the inverter uses then is a 2s2p configuration to provide a nominal 192v input to the inverter. This might be 192v either side of zero or 192v with, effectively 2 packs in parallel.
Output from the inverter is 8kw at 240v AC.

My aim is to convert the battery packs to li-ion using 18650 cells. The way I worked out the voltages suggests I use 28s6p setup in each cartridge. I therefore need a battery management system that can be used for each cartridge. Eventually I plan to have up to 44 of these cartridges in the system, so needs to be relatively cheap and /or expandable. I am happy to solder stuff together if need be.

Any suggestions? Thanks in advance

[doobedoobedo]

What about Stuart Pittaway's diyBMS?

Try searching youtube for 'Adam Welch solar shed' too as he's made some videos about using it.

[Mechsman]

Doobee, many thanks for the suggestions. I had a quick look at Stuart Pittaways one, looks like its set up for 48v packs, unless I'm missing something?

[doobedoobedo]

looks like he's got a new version out, around 4:40 he states up to 64 modules.