batteries

[g_man1146]

Hi Don,
To add a little more to the battery question:

As the name implies, Starter Batteries are meant to get combustion
engines going. They have many thin lead plates which allow them to
discharge a lot of energy very quickly for a short amount of time.
However, they do not tolerate being discharged deeply, as the thin
lead plates needed for starter currents degrade quickly under deep
discharge and re-charging cycles. Most starter batteries will only
tolerate being completely discharged a few times before being
irreversibly damaged.
Deep Cycle batteries have thicker lead plates that make them
tolerate deep discharges better. They cannot dispense charge as
quickly as a starter battery but can also be used to start
combustion engines. You would simply need a bigger deep-cycle
battery than if you had used a dedicated starter type battery
instead. The thicker the lead plates, the longer the life span, all
things being equal. Battery weight is a simple indicator for the
thickness of the lead plates used in a battery. The heavier a
battery for a given group size, the thicker the plates, and the
better the battery will tolerate deep discharges.
Some "Marine" batteries are sold as dual-purpose batteries for
starter and deep cycle applications. However, the thin plates
required for starting purposes inherently compromise deep-cycle
performance. Thus, such batteries should not be cycled deeply and
should be avoided for deep-cycle applications unless space/weight
constraints dictate otherwise.
Xantrex, the maker of inverter/chargers tells us NEVER to charge GEL
or AGM batteries at the Lead-Acid battery voltage. That said, I have
to say that my coach has 6 group 4D Gel batteries that are original
('99) and still performing as new. They are charged by the Xantrex
units (two 3000W inverter/chargers with a total of 320 amp output)
set for "Gel" voltages. When on shore power for weeks at a time, the
additional three 12 VDC Lead-Acid maintenance free batteries for
starting stay at nearly 100% using an Echo-Charger from the same
charging source. When running down the road the 300 Amp alternator,
which is set to Lead-Acid charging voltage, has not hurt the Gels.

Rich D. '99LXi43' CT





--- In WanderlodgeForum@yahoogroups.com, dspithaler@a... wrote:
>
> Rich When I got my 89 SP 36' it had 4-12 Volt Deep cycle
Interstate for
> the house in the front compartment & 2- 12 Volt Deep cycle in the
rear for
> the Cat starting batteries. The house batteries had 2 that were
weak so I
> changed the 4 to 4-- 6 Volt Trojan batteries & left the 12 Volt
deep cycle in the
> rear as they were good. Was that a bad idea??? Now two years
later I am
> going to change the Starting batteries to 2--12 volt Interstate
starting
> batteries as I thought they are better for starting than the Deep
Cycle. Is that
> going to work & be good?
> Don
> 89 SP 36'
> Butler, PA
>
>
> [Non-text portions of this message have been removed]
>