Battery recovery?

I have a 2007 E2 that had an original set of batteries that lasted 7 1/2 years. I replaced the set a little over 2 years ago and they never really charged properly it seemed. The batteries are Deka 8G31’s. If I run the vehicle after a full charge, I can get a little more than 9 holes of golf in and I can tell the system is getting really sluggish. Then when I place it on the charger, Delta QuiQ, starts then goes to a 4 red led flash error. I then have to individually charge each battery then reconnect the AC charger and it will eventually finalize the charging cycle. But after another run on the course it’s the same situation.
My question is, should I change the algorithm to a gel recovery mode and see if that will help the batteries or is it to the point that a new set is needed?
I appreciate any help.

You might have a dud battery, What is the pack voltage after charging you should see about 80 volts. I assume you have looked for dragging brakes etc.

You might do a brake load test to check each battery.

After a complete charge, the pack reads 83v. The charger has gotten to a point now that it will charge but then give 3 red flashes saying it took too long. I have not done a brake load test. What is the proper, best way to do this test?

Pretty sure old house boater means that you should check your brakes. Jack up the vehicle and make sure each wheel is spinning freely without excessive drag.


Attach Volt meter to (1) battery Stand on the brake and hit throttle for 2 seconds. Read and record voltage. Repeat on all batteries. A bad battery will stick out like a a sore thumb.

Thanks for the tip. I found 1 battery that would drop to zero on the brake test. The remaining 5 would drop from 12.8v to 12.34v. I’m replacing the bad battery and will check the loads again after a good couple charge cycles.

I learned something today. Good thing to know.