[RE-wrenches] FLA battery problelm

David Coale david2coale at gmail.com
Fri Dec 12 10:18:55 PST 2025


Hi Wrenchers,

I have a client with an old off-grid Trace system and he is having trouble with the batteries.  He has HUP Solar One FLA batteries that are about 4 years old, so they should be in good shape.  The last set lasted almost 20 years with a fair amount of abuse.

Here is he history and what I think is going on. 7/21 they got new batteries after about 19 years of use.

7/22 I get a call saying the batteries are not charging up all the way.  When I check out the system, the batteries needed cleaning, and I found three low cells, and the charger settings were back to default, not set high enough to charge the batteries all the way (it’s always multiple problems).  The client (now a new renter, new to the system) said he was filing the batteries once a month and experienced some overflowing when the batteries were charged up.

I cleaned things up, reset the charging parameters and set up an equalizing charge to even out the cells. Hopefully this will fix things.

11/25. The client calls and said the batteries don’t charge up all the way and he is running the generator a lot and worried about getting though the wintertime.
When I check things out, there are three bad cells and there is soda on the batteries. It is hard to get a good voltage readings because of the soda. Most of the cells are reading 2.1 volts under about a 40 amp load.

Yesterday I check things out, and all the cells are reading between 1.93 to 1.98 under a 40 amp load in the morning, and I don’t find any bad cells.  The charging voltage is never going over about 52 volts so the system is never getting fully charged up.  The charge setting look OK, so not sure what is going on. This is acting like an old battery pack but these batteries are relatively new.

My guess at this point is that maybe the batteries lost acid with the overflowing event and lost capacity.  Maybe adding acid back in would bring them back up to working order.  The SG measured at 1.150 or less.

At this point the client (renter) has had enough of these battery problems and is wondering every morning if the batteries will last long enough to until the sun comes up.  The renter is pushing for a replacement LFP battery, but there should be lots of life left in this battery pack.

Let me know what you all think.

Thanks,

David




More information about the RE-wrenches mailing list