question

Hello @Obo and @Guy Stewart (Victron Community Manager),

I understand Obo questions as I'm on the same case.

I understand that there is a lot of lithium battery or cells manufacturers but a validation of 1 unbrand battery/cells manufacturer can help Victron customer with general wiring recommendation, Victron material to use and Victron product parameter.

I will try to use a 16 Lifepo4 cells + BMS + BMV-700 plugged on a Multiplus 2 48/3000 and if this global system does not work I will not know if the problem comes from BMS / BMV-700 or Multiplus 2.

I don't speak about a detailled wiring illustration or a detailled parameter setup for every possible configuration but general requirment from Victron for other unapproved battery can help.

The "real" LifeP04 batteries cost considerably more that the unbranded made in China. (Bear in mind the majority of cells are made in china). The main deficiency in the cheaper ones is their relatively dumb internal BMS. However having a Quattro make solving that deficiency quite simple.

What is missing is a trigger from the batteries BMS to tell the Quattro stop the charging. Quattro in its "Assistants" offers a couple of solutions. The two signal BMS support assistant can either "Force to Float" or "Disable charger". I used a programmable voltage sensitive relay to close contacts when the battery voltage was stable at 14.2. It cost the princely sum of $25. The purists will no doubt explain that I am not achieving the maximum charge, which is true. But charging to 96% at a fraction of the cost of the "Real" lithium was a perfect solution.

The wiring was simple and the config easy.

I have removed 6x140A AGM and now run 2x200A LifeP04 and all is good.