I am in the process of checking all my remaining batteries for maximum charge. Not too bad. The worst is about 2900mAh, the best so far my NuPower #1 that had 5950mAh. If I keep using them in rotation, I hope to keep them running for several more years. Looks like fewer new batteries are being made than a year ago... Eventually will be like my 1400s, just usable when plugged...Pismos are great, I want to keep using for as long as I can. Thanks for the great info, folks. I won't try rebuilding a li-ion battery, that sounds too complicated for the likes of me.