I have an older set of first gen milwaukee V18 lithium ion batteries. They're 5-6 years old and I wanted to see about getting the batteries reconditioned. Or has anyone replaced cells on their own? I have a young helper that is just getting started in the trade. I was going to get these batteries fixed up and give him a set of cordless tools. I have another set of newer milwaukee M18 and newer dewalt xrp so these have been sitting in the cold shop for awhile. The tools currently work great still but the batteries take a while to charge and don't hold a charge very long. They're also lacking in the power dept big time. Anyone have experience with this?