Extra battery dies fast

[Mduvall219]

I added a 7th battery to my 2013 ezgo. I can ride about 4 miles with plenty battery than it drops drastically. The added battery will be about 7v and rest are still 8.3v. Anyone have any idea why?

[swb713]

What is the condition of the 7th battery?
Sounds like it is not in great shape to begin with, but I'm no expert.

[cgtech]

Is it newer or older than the others? Is it the same AH capacity? You are using a 42v charger, right (not a 36v charger & charging the other one separately)? Fully charge the batts & report the voltages to the second decimal point (6.XX volts) after allowing them to rest for 12 hours.

[Mooncarter]

Originally Posted by cgtech

Is it newer or older than the others? Is it the same AH capacity? You are using a 42v charger, right (not a 36v charger & charging the other one separately)? Fully charge the batts & report the voltages to the second decimal point (6.XX volts) after allowing them to rest for 12 hours.

He said the others are at 8.3. He must be trying to run at 56v? IDK.

[ThreeCW]

Originally Posted by Mduvall219

I added a 7th battery to my 2013 ezgo. I can ride about 4 miles with plenty battery than it drops drastically. The added battery will be about 7v and rest are still 8.3v. Anyone have any idea why?

I'm "assuming" that the 7th battery was added in series to the other 6 batteries. And "assuming" you are using a 48 volt charger to charge 56 volts worth of batteries, which will not be providing a full charge to any of the the battery pack ... hence it could be part of your reduced range problem.

Since the 7th battery is down to 7 volts, it is at less than a 10% state of charge ... which is essentially dead. Batteries in series are like a chain ... only as strong as the weakest link. And that 7th battery is the weak link which is limiting your battery pack.

It sounds like a science experiment gone bad. I would suggest going back to the your original 6 battery pack.