We have gone from Lead Acid to Victron NG batteries. 2 x 300Ah in parallel.
I note the manual says to charge independently for commission charge for SERIES connections, but its completely silent on PARALLEL. I have asked a few local people and had mixed answers, so thought I would check out what the experts here say.
Thanks
While in a perfect world if you have the kit, charging them separately first is a good idea I did not charge my 2 x 300Ah NG separately. They should both arrive around 45% SOC. Check that they both have the same voltage, which they should do. If they are within 0.05V then less than 50A should flow so that they can be connected together. If there is a few % SOC difference then this will balance out towards the end of charge.
I took my first charge with a max 100A charge current into both batteries. A couple of useful tips, set your battery monitor to 45% manually before you start so you have a rough idea, if you leave it at 0% or 100% you are blind. Secondly, if you have a Lynx NG BMS, this actively controls the charge and if the cells are not well balanced it will extend the absorption time, mine had a 5 hour initial absorption. If the cells are well balanced, absorption will be reduced, it only absorbs for as long as required to balance the cells.
Great answer thank you. I will let them charge together with that long absorption time, then disconnect them and connect them individually for a while to make sure they are both full.
From memory all cells in batteries were at 3.3 with 1 cell at 3.29.