Lipo unbalanced
 

I have a Gens Ace 7.4 5000mah. Had it about 18 months and run it about once a month at club meets. Always balance charge it at the correct ampage and store it correctly although lately its been stopping and detecting a low or high cell voltage. Also charging now the voltage jumps 8.20, 8.15, 8.20,8.15 etc which seems to me it's unbalanced somehow. Does this mean the battery is done and I should get a new one? How long do lipos last?

Thank you

You might want to double check that one of your charging cables isn't going bad, or that the terminals on your battery are not damaged. I've had that behavior caused by a bad balance terminal on the battery. The charger wasn't always able to get a reading off the balance port and would throw high cell voltage alarms, while the individual cell voltages would be all over the place.

Hmm yeah that's a good point. I will check that out. Thank you.

Check the Charger balance wire end that goes to the battery. Gets handled a lot and wire can break inside heat shrink.

I would worry about it. As long as it isn't bloated out. I've been using lipos along time now, about 6 yrs. cells of 3.2v.You'll never see cell that balances the same. It does matter you'll get the same C rating out of it. When it discharged or run down till cut-off voltage what ever manufacture of charger you have, it'll stop at 3.0v. The average of the 2 cells, ie, reading per cell 3.2v and 2.8v average of 3.0v. All lipo charges to the max of 4.2v and never more. you can top it off, by restating the charger if you're so anal about it. C rating of lipos are good you do get what you pay for.

most ESC has cut-off voltage set at 3.0v high end ESC up to .1v increments, mine set at 3.2v. I still use 3200 lipos 5yr old lipos, this year 5000-5200mah on my car, never had problems, soft or hard covered lipos.

My opinion of it.