I got my Bionx with battery in early August of 2008. It's a PL (lithium) 250, so the battery is supposed to take me about 18 miles on power assist number 4. I've ridden it almost 500 miles now, and the battery isn't holding up. I'm figuring it has gone about 30-40 cycles. On the last trip of 10 miles, the charge was almost gone by the time I got home. It's cold now, and I know the batteries don't do so well in the cold. However, it's Phoenix-type cold, which means temperatures in the 40's and 50's. (That's above zero in Farenheit.) I did also run it down to zero bars one time.
The battery has a year warranty. Should I send it back?