Converting a Solar Lead Acid GEL battery system to Lithium

[VK2RK]

Importing and commissioning Lithium presents several problems that will send you down the rabbit hole, in the end the cost saving is huge offsetting the pain experienced making it worthwhile.

Old Lead acid system 800 Ah at 48 Volts art 50% discharge useable 19.2 KWh

Lithium system providing 21.4 KWh

Conversion from Lead Acid to Lithium
At first the conversion seemed straight forward as the Inverter/Charger does provide for either managed Lithium or self-managed Lithium.
little did I know I was about to go down the rabbit hole.

Full Article

 

[VK3YNV]

Nice work, the top balancing issue is one that I would have missed. But obvious in retrospect.

Interesting read. Thanks

 

[VK2RK]

Nice work, the top balancing issue is one that I would have missed. But obvious in retrospect.

Interesting read. Thanks

At first the whole thing had me tossed, I had no idea why the system was shutting down and Selectronic was not of any real help but to lower the charge voltage. In general it was one large stuff-up with issues from charging to communicating with the packs.
Faulty cables from the manufacturer (4 of them ) wired wrong, that had me going, I should have known better from China
Again it was worth the pain as the dollar saving was huge.

 

[VK2RK]

As an update, after just over a week having configured the BMS's to not shutdown due to cell overvoltage allowing the cells to balance to each other, the result is that those cells that rose above 3.7 volts are no longer doing so remaining within 20 mV of all other cells.
The BMS's parameters have now been returned to factory settings.
Happy camper I am.