keystone battery holders are not too friendly with the vtc5 batts. the clips tail or whatever its call got under the battery and shorted it. The tail is straight so it can easily get under the wrapper on a vtc5. Don't know who is really to blame, sony for wrapping the battery or keystone for a miss design. Don't think the sony vtc5's are inteded to be used in battery holders, think they are intended to be hard wired in battery packs for cordless drills and stuff like that, maybe somebody here knows. Comparing them to batteries like efest that buy cells and then just rebrand them they have a lot better wrapper. Top one is the original one, bottom one is modified. Poor vtc5 I mangled it trying to get the frigging thing out.