[Mgs] batteries: lead-acid vs Absorbed Glass Mat

[Stuart MacMillan]

AGM and Gel batteries have one advantage over flooded batteries, and that is
they will survive deep discharging (80%) many more times than a flooded
battery will.  So, they are best for applications where that is a frequent
occurrence.  They also need a higher charging voltage than most cars (ours
included) put out, at least 14.2v, and 13.6v is typical for most cars.
Without the higher voltage, they never fully recharge, and their life
shortens drastically.  You either have to kick up the output of your
alternator, or use a special charger designed for Gel and AGM once a week to
keep them alive.

IMHO, it's best just to stick with a flooded battery.

Stuart

-----Original Message-----
From: mgs-bounces+macgroup=comcast.net at autox.team.net
[mailto:mgs-bounces+macgroup=comcast.net at autox.team.net] On Behalf Of Paul
Root
Sent: Sunday, August 17, 2008 9:24 AM
To: MG List
Subject: [Mgs] batteries: lead-acid vs Absorbed Glass Mat

Seems my battery has died. I've been having some issues, that I  
chalked up to my recent re-wiring of the radio.
And then some short in the ignition switch and/or light switch.

I finally left it on the trickle charger over night, and it won't hold  
a charge. That's ok, it's 5 years old. I got my use out of it.

The battery is an Interstate, and worked well for 5 years, even during  
last years alternator failure. I actually think that the alternator  
started going out the year before, which may have contributed.

It's not a group 26, so it's a little big, but goes in. No handle, but  
I have a rope around it to help get it out. Still, I need to use a  
little hydraulic jack to help.

Anyway, to the question. Is there a great advantage to going to a AGM  
battery (Westco or Optima type)? Apart from size?  I think
James got one fairly recently. Do you like it?

Would a battery for a Miata work? Or is there a different size that's  
better?

Paul.
Mgs at autox.team.net
http://autox.team.net/mailman/listinfo/mgs

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