On Thu, Jan 5, 2023, 16:22 Keith Lofstrom <[email protected]> wrote: > I have an ancient Tripplite 700VA UPS, which is briefly > triggered maybe twice a year, and needs a new sealed lead > acid (SLA) battery maybe every two years. ... > New technology LiFePO4 batteries last much longer and are > environmentally cleaner than an SLA, and are shape and > terminal compatible, but they charge differently. ...
On Thu, Jan 05, 2023 at 06:38:52PM -0500, Tomas Kuchta wrote: > I came to the same lithium based battery UPS conclusion - there are no > easy, economical, reliable and save choices. ... > My solution is to get and wire external marine deep discharge battery to my > UPS when I need to replace its internal SLA battery. They play nicely with > the UPS and should last about decade for the similar cost to SLA. ... Keith Lofstrom responds: Shades of the past - I did the same thing 30 years ago. I have a "dumb" shoebox-sized device designed to work with marine batteries. It worked so well that I forgot to maintain the batteries, and they sulfated. I can imagine designing a smarter device managed by an Arduino rather than a forgetful owner, but can't imagine finding the time to design and build and "Make Magazine" it. I can also imagine designing an Arduino-ish "power shim board" that sits in between the terminals of a LiPO4 battery and the plugs of a UPS designed for SLA, which transforms voltages and currents and impedances so that the combination "looks like" a SLA battery to the UPS. That costs even more time, which I have better uses for. The Tesla Powerwall is an exuberantly extreme version of that, and I can imagine gubmint/utility mandates/subsidies and variable power pricing with buyback making a ($15K retail?) Powerwall pay for itself in the long-term. OTOH, I don't want a potential medium-yield bomb hidden in the house. Outside, when a resale market for Powerwalls develops, catalytic converter thieves will develop another profit center. Then I must trap them and sell their organs ... not the direction I want to go in life. :-( Ah well. Time to buy a cheap SLA battery, fix up my old SLA UPS, then send a check to Nature Conservancy to assuage my lead-acid eco-guilt. The LiPO4 batteries can power a slightly modified-mobility scooter, which a relative may be needing soon. Keith -- Keith Lofstrom [email protected]
