[TriLUG] recommendations for UPS 12V batteries?

Thu Apr 23 16:03:52 EDT 2020

Has anybody looked at LiFePO4 as a lead acid replacement?  I have looked at
doing it, but have not.

Good luck,
Charles Fischer

On Thu, Apr 23, 2020 at 3:15 PM Wes Garrison via TriLUG <trilug at trilug.org>
wrote:

> Through my (limited) knowledge of these things, a higher float voltage over
> long time periods does much more damage to battery longevity than a higher
> charge voltage for most applications where you discharge relatively
> infrequently but are constantly applying float charge.
>
> I've been using a nice Tripp-Lite 48V Inverter with expensive 150AH AGM
> batteries for 4 years, and the slightly higher float voltage killed the
> batteries after just 4 years instead of the expected 10+.
> Here's the inverter:
>
> https://tripplite.com/2400w-powerverter-aps-48vdc-120v-inverter-charger-auto-transfer-switching-hardwired-ul~APS2448UL
>
>
> It's a "square-wave", not a true sine-wave, but my computer equipment
> doesn't care.
>
> The batteries call for float voltage of 54V - 55.2V, and the charger
> supplied 54.4V (so it claims; I didn't measure), so technically on the low
> side of the acceptable range, but still high enough to cause an early
> death.
>
> I now have new 60AH AGM batteries (much cheaper) running with the same
> inverter but using an external charger specifically configured for AGM
> instead of a more generic "gel" setting.
>
> We'll see how much longer they last...
> _________________________________
> Wesley S. Garrison
> Network Engineer
> Xitech Communications, Inc.
> phone:  (919) 260-0803
> fax:       (919) 932-5051
> __________________________________
> "Lead us not into temptation, but deliver us from email."
>
>
> On Thu, Apr 23, 2020 at 2:15 PM Joseph Mack NA3T via TriLUG <
> trilug at trilug.org> wrote:
>
> > On Sat, 18 Apr 2020, Pete Soper via TriLUG wrote:
> >
> > > Yars ago I instrumented a couple UPS devices to see how the behaved. I
> > recall
> > > one that was in the wrong county with respect to float voltage. Too low
> > and
> > > the electrodes accumulate sulphate and die. Too high and the water is
> > > disassociated and driven past the pressure release as gas, leaving the
> > > electrolyte short of ions. And the float voltage needs to be
> temperature
> > > compensated.
> >
> > I took out my two APC 700s, in which the batteries only last 2 years.
> >
> > They have two batteries in series.
> >
> > On float, one had the batteries at 14.0V and the other at 13.8V. I would
> > accept
> > anything between 13.8 and 14.4V. I was pleasantly surprised that both
> > batteries
> > within each UPS had the same voltage within 0.05V (If one goes low, then
> I
> > assume the charger will hammer the other one.) The batteries weren't
> warm,
> > so I
> > assume the UPS is being nice to them.
> >
> > So it would seem that these two APC UPS is doing the right thing as far
> as
> > the
> > batteries are concerned.
> >
> > I then took out my unit in which the batteries lasted 10 years.
> >
> > It has float V=55.0 (4 batteries in a bank. I didn't open it to measure
> > each
> > battery) = 13.75V/battery.
> >
> > It would be interesting if a difference in float V of 0.1-0.2V/battery
> was
> > making all the difference.
> >
> > Joe
> >
> > --
> > Joseph Mack NA3T EME(B,D), FM05lw North Carolina
> > jmack (at) wm7d (dot) net - azimuthal equidistant
> > map generator at http://www.wm7d.net/azproj.shtml
> > Homepage http://www.austintek.com/ It's GNU/Linux!
> > --
> > This message was sent to: Wes <wes at xitechusa.com>
> > To unsubscribe, send a blank message to trilug-leave at trilug.org from
> that
> > address.
> > TriLUG mailing list : https://www.trilug.org/mailman/listinfo/trilug
> > Unsubscribe or edit options on the web  :
> > https://www.trilug.org/mailman/options/trilug/wes%40xitechusa.com
> > Welcome to TriLUG: https://trilug.org/welcome
> --
> This message was sent to: Charles Fischer <cfischer at modernferrotype.com>
> To unsubscribe, send a blank message to trilug-leave at trilug.org from that
> address.
> TriLUG mailing list : https://www.trilug.org/mailman/listinfo/trilug
> Unsubscribe or edit options on the web  :
> https://www.trilug.org/mailman/options/trilug/cfischer%40modernferrotype.com
> Welcome to TriLUG: https://trilug.org/welcome