How long can a Rad battery last? A long time.

[DickB]

I tested the Standard Battery on my Rover 5 when it was new, and now again after 5+ years and about 5000 miles on this battery. (I have 8700 miles on the bike, but have two batteries which I occasionally swap.) The battery has not noticeably degraded.

The test consists of my riding the bike throttle only fully open on level roads until it virtually quits. I stop every two miles and measure the battery voltage after 60 seconds. The battery is still performing like new, except for the last few miles.

I ride 12 miles most every day, and charge to 80% after every ride. The bike lives in my garage in Florida, so it is subject to 80+ degrees (often 90+) nearly all year. I have a meter on my charger that shows that the charger adds about 110 Ah on a charge, which is about 1/6th capacity. So I'm doing the equivalent of one full charge every 6 days. That works out to about 335 full charge cycles. Rad advertised 800 cycles on the battery when I bought the bike; the cell manufacturers say 500 cycles.