Got a thwaites 6 ton dumper, thats battery has had it, tried to recondition it, charge it, dont really want to by a new battery because, as its rarely used, will a fast charge, start it, or would this be an ideal job for those "booster packs" you can get, if so what model, type, price etc, from users experience would be a good model to maybe think of buying and ones to avoid? Comments please for me and im sure going into the winter period others would be interested?