New Battery Maint

[tx63conv]

I bought a new set of batteries for my EZ-GO over the weekend (ouch). In an effort to better maintain these batteries, I wanted to make sure I keep them charged correctly.

I have read to not let them get below 80% which I believe would be about 37.5v on the pack--according to the state of charge table on the EZ-GO website.

I ran around the neighborhood for about 20 mintues last night and the pack went from 38.7v to 38.3v. I did not put the pack on the charger.

Should I let the pack get down to 37.5v and then charge or just put it on the charger after every use? I use the cart for about 10 minutes twice a day to drive my daughter to school and pick her up.

I am concerned that my charger will not turn off--I have never let it run until it turned off (I let it run overnight once and it never did) but I have had battery issues in the past.

[Larry1950]

Most chargers are on a 12 hour timer before they shut off. More important is the current showing on the meter. The meter should be around 20 amps at the beginning of the charge, tapering to about 4 - 6 amps over the time of the charge. The batteries will handle 4 -6 amps for a very long time. If you are charging still at 20 amps over several hours there is a problem with the charger or batteries. As more or less a a rule of thumb for every hour of run time you will need 3 to 4 hours of charge time. New batteries will take 20 to 50 charge cycles before their full potential is reached.

[tx63conv]

Thanks for the input. Given my usage (2 trips at 10 min each on flat terrain), do I need to charge every night or is it safe to monitor the pack voltage and set to charger every few days?

[gaminde]

You drive the cart you plug it in when done, even if its 3 feet.

[Larry1950]

Yep!

[gaminde]

I just reread you post so you never let them charge all the way and now you want to go down to 37.5 and the voltage is at 38 now you are doing all the wrong things.
6 batteries 3 cells each = 18 cells total x 2.32volts per cell =41.76 volts charge at end of cycle, which you not letting this happen, and batteries should level off around 40+ volts after 6 to 8 hours this is not happening. Please don't go down to 37 unless totally necessary to get home.

[tx63conv]

Understood on the charge after usage.

41.76v? I just installed these batteries new yesterday and they only read 38.7v. The chart in Table 1 on State of Charge on the ezgo website reads 100% as 38.20v.

What am i missing here? Help me understand so I dont waste a brand new set of batteries.

[gaminde]

Understood on the charge after usage.

41.76v? I just installed these batteries new yesterday and they only read 38.7v. The chart in Table 1 on State of Charge on the ezgo website reads 100% as 38.20v.

What am i missing here? Help me understand so I dont waste a brand new set of batteries.

Yes that's my bad I was thinking 38 not 36, I usually only work with 48. My chart shows 38.22 so your are correct, but the finish charge should be 2.25 to 2.35 volts per cell depending on the maker of the batteries so you must let it charge till shutdown.

[tx63conv]

ok, you had me worried. I will put on the charger tonight and test. Thanks for the help.

[gaminde]

That's Ok you had me embarrassed

[wthompson]

Don't forget to water the batteries! keep it above the plates. As gaminde said charge them everytime you use it, if you use it everyday charge it every night but don't go below 70-80% SOC, and let the automatic charger run until it turns itself off.