12v 100ah Battle Born Low Voltage Problems

Koolchange

My Multiplus II 12 I 3000 | 12v low battery light goes on everytome I turn it on. Explorist.Life checked the cable connections at the Hood River Van Expo in June and everything was ok. The problem continued so I ran Battle Born's diagnostic light test using my Victron smart charger. I charged the (4)100ah 12v batteries using custom settings provied by Battle Born, recorded the voltage, continued charging for 45minutes, removed the charger, and using a multimeter tested the voltage with 12v DV test light connected. The following are the results: Battery #1(new) - 14.40v, 14.40v, 11.59v, Battery #2 (new) - 14.40v, 14.40v, 9.60v, Battery #3 (lightly used) -14.40v, 14.40v, 5.49v, and Battery #4 (lightly used) - 14.40v, 14.40v, 1.76v. I had a few shorts during installation so I am not expecting the batteries to be covered by warranty.  Does anyone have a suggestion how I can recover any of the batteries? Thanks. 

Grumpy_G

Remove the connections between the batteries and charge them individually. The charger only puts out 15A AFAIK so charge each battery for a day.

Edit: Actually there are different chargers with different max outputs. Which one do you have ?

Koolchange

Victron Blue Smart Charger

Grumpy_G

You do realize there are over 20 different "Victron Blue Smart Chargers"... ?

Koolchange

No. It is IP65 12/15(1) 120V NEMA 1-15P Retailer.

Grumpy_G

That is the 15A charger. Under ideal conditions it should be able to fully charge a single empty battery in less than 7 hours. Three of the batteries are under the discharge cutoff voltage, they need to "wake up" so definitely charge them individually. AFAIK the phone app shows the charge current so you can monitor progress.

Koolchange

Thanks for the help. I will let you know how it gos.