On Mon, 02 Apr 2018 12:11:30 -0700, moshe.braner wrote:

In your test, did you measure the AH capacity in the discharge or the
recharge? The latter is of course generally an overestimate.

The Yuasa had to be really well made to last THAT long! Half the life
at half the cost may be OK too though. 6 years is not bad.

The practical life of an SLA mostly depends on how it is treated, not
the manufacturing quality. I've seen our club's batteries go dead in
less than 2 years. I think that's in part due to sometimes being left
in a glider that it tied out, where it gets quite hot. I left a spare
battery in my glider trailer for one season, it was then dead, again
perhaps due to heat. Other than keeping them cool (but not cold), make
sure to fully charge right after use (within a day or two anyway), using
a good "smart" charger that will not overcharge it.

I do a fully charged - discharge - recharge cycle once a year on my
batteries (Yuasa NP7-12 SLAs) and sling them when they drop below 2/3 of
the capacity measured when they are new.

I use a cheapish multi-chemistry charger of the type sold for charging
and monitoring RC model batteries, so its good for round 0.4 amp charge
and discharge rates. Mine is a Pro-Peak Prodigy II sold in the UK by
Ripmax and is now several years old (12 at a guess). Similar charge/
discharge units will be available almost anywhere.


--
Martin | martin at
Gregorie | gregorie dot org