http://www.amazon.com/Garmin-DC-30-Battery-Pack/dp/B001BW26DUBefore you go buy a new battery, call Garmin. I had one collar that did not charge correctly a couple times. The collar was over a year old, and out of warranty. I called Garmin, and they send me a brand new replacement battery, at no charge. However, the collar started working fine before I ever put the new battery in. Now I have a new battery sitting in storage, waiting on an original one to fail. In hindsight, I think I might have had some crud built up on the contacts not allowing the battery to take a full charge in the same time as the other collars.
