I got this battery for my k13 and it's much lighter and cheaper in construction than my previous bosch batteries. Notice where the handle folds down. Normally there is a square plastic bit there that makes it hard to accidentally connect a spanner across the terminals. Now that the plastic bit is gone, it's easy to connect a spanner across the terminals. That's exactly what happened to me today. I had the handle in the up position and when connecting the positive terminal, the end of my spanner accidentally connected to the negative terminal. It got pretty hot and I burned my finger trying to get it off. Needless to say I will be using an insulated spanner from now on.
