Re: (ET) 12 Volt batteries!

[Tim Humphrey <hump evgrin com>]

  Here's my experience with new never used 6+ yr old batteries.
 
 These were Hawker Genesis batt's, I could reasonably expect any other
 brand to not fair as well as these...
 
 I received them in their unopened factory shipping boxes, they are all at
 least 6 yrs old.
 
 If the open circuit voltage read 11 or better, I had a 99% success rate
 just plugging them into a Schumacher SpeedCharge charger
 http://store.schumachermart.com/sc-1200a.html (bought at Wal-mart). One
 note though, they don't sit at 12.80 like Hawker says they should, they 
rest at
 more like 12.69-12.74. BUT!! I haven't cycled them, just charged them,
 with a little exercise I expect them to increase.
 
 Open circuit voltages of 8.5 - 11 were about a 65% success rate.
 
 Below 8.5 was about 10%.
 
 The batteries below 11v were put on the charge scheme that David pointed
 out, up to 80 volts through a headlight, until the current started to
 rise, then the light was removed and the V reduced to 14.7 - 15 manually 
kept
 constant (I used the Mil Surplus charger, commonly referred to amongst EV
 and ET'rs as a Fair Radio charger) until the current started to drop, then
 it was placed on the Schumacher..
 
 Dead batteries here in NY are good for an $8.00 core charge. So if they
 were free and not usable, they'd still be worth 8 bux.
 
 I'd go get 'em.
 
Stay Charged!
Hump
I-5, Blossvale NY
 



> 
> 
> 
> -----Original Message-----
> From: elec-trak-bounces cosmos phy tufts edu
> [mailto:elec-trak-bounces cosmos phy tufts edu] On Behalf Of David Roden
> Sent: Monday, March 19, 2007 10:55 PM
> To: elec-trak cosmos phy tufts edu
> Subject: Re: (ET) 12 Volt batteries!
> 
> On 19 Mar 2007 at 16:28, Kleinbrahm, Robert wrote:
> 
>> Does anyone know the shelf life of large AGM type batteries.
> 
> They're like any lead battery - if they self-discharge and are left
> discharged, they'll become sulfated.  There's no cure for that.
> 
> The good news is that most AGMs have appreciably lower self discharge 
> than
> flooded or gel batteries.  Six years is a prettly long time, but as a 
> wild
> guess, I'd say they have a 30-50% chance of retaining enough capacity to
> make them useful for light duty use.
> 
> They'll most likely be dead flat or nearly so.  To try to bring them 
> back,
> you'll need a moderately high voltage power supply.  Connect an 
> automotive
> taillight in series as a current limiter and crank up the voltage until
> you
> see a little current flowing.  If you're lucky, after something between
> several hours and several days, the current will start to increase.  Then
> you can start turning the voltage down.  Once they get a bit of a charge
> on
> them, you can switch over to a real charger.
> 
> If someone offered them to me for nothing, I'd take them.  I wouldn't pay
> anything for them, though.  Hey, if nothing else, they could be useful as
> ballast in the ET weight box.
> 
> David Roden - Akron, Ohio, USA
> 
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> Note: mail sent to the "etpost" address will not reach me.  To send
> me a private message, please use the address shown at the bottom
> of this page : http://www.evdl.org/help/
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> In politics stupidity is not a handicap.
> 
>                                       -- Paul Graham
> 
> = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = = =
> 
> 
> 
> _______________________________________________
> Elec-trak mailing list
> Elec-trak cosmos phy tufts edu
> https://cosmos.phy.tufts.edu/mailman/listinfo/elec-trak
--