Problem charging lithium battery

hi just put 75/15 system on with 350w panels to charge roamer 460 lithium battery but it will not go over 48% can anybody help or had the same problem thanks

You have a 460Ah battery and are trying to charge it with a 15A charger. If it was down to lets say 20% then it has 92Ah in the battery and needs 368Ah adding to fill it up. At 15A, assuming you always have good enough sun it will take 25 hours of full sun to recharge it fully, so maybe 3 days. If you keep using power you will never get it full. You need a larger charger with more panels to charge such a large battery.

OK but had it on the van with nothing on and will not go over 49%

What voltage are you getting up to during charging. I have heard some comments about SOC accuracy of some of the cheaper batteries during initial charges.

23/24v solar

OK so panels are producing, but what battery voltage when charging is taking place and after sun has gone down so we can work out if the SOC reported is correct.

14.44 on the victron app roamer app 13.08

That is really odd, the solar charger believes it is fully charging at 14.4V but the battery voltage at 13.08 is closer to 50%.

  1. Check the fuse on the outlet of the controller, is this blown as this would give your symptoms. See picture below, it is the orange item in the lower left. If the fuse is blown it may be because the 15A controller is working flat out continuously to charge the very large battery.
  2. If the above is OK, check your wiring between controller and battery for loose connections or isolators or other fuses. If you have a multimeter this can help identify issues.
  3. If 1 and 2 are good then see if the battery has disconnected charge, I am not familiar with Roamer but the app should tell you that it is OK to charge.
  4. If 1 and 2 and 3 are OK then I am stumped.

Thank you will do

Had a chat to solar 2 go have to try and wire the panels in parallel and change the settings on the victron to lithium