That's a very good point, John. Battery "calendar life" is exponentially dependent on temperature. The original poster did say that he didn't expect deep discharge because the UPS would signal the backed-up equipment to shut down within minutes of the power failure. On Sun, Jun 30, 2013 at 11:10 AM, John Gardner wrote: > As well as charging tempco, ambient T is significant for > > longevity - Trojan claims (for their deep-cycle lead-acid > > batteries) that the longevity & charge capacity lines cross > > @ 77=BA F; lower T lengthens life, at the expense of capacity. > > You did'nt mention the depth-of-discharge you anticipate... > > -- > http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist > --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .