My first T-Mobile Dash battery went bad after about a year of use. This was around last March or April (2007). I bought a new replacement battery through T-Mobile around that time. Today, I noticed that my battery was at 2% charge after turning it on. I had fully charged the battery the night before and turned off the phone after the battery was charged. I fully charged the battery after noticing this and then used it like I normally do. The battery was down to about 50% at the end of the day (night). Normally, the battery is between 70 and 80% capacity after a 14 hour or so period.
This sudden drop in charge capacity is very similar to what I saw in the original battery when it started to go bad. However, this time the second battery went bad in less than 7 months of use. That seems awfully short to me. I’m not going to buy a third battery, however. My T-Mobile G1 (Google Android) phone should arrive sometime next week. So, I’ll either switch to a different phone or muddle along with awful battery life for another 10 days or so.