>In a message dated 97-07-03 19:56:35 EDT, wkube@iadfw.net (Wayne Kube)
>writes:
>
>> But, if you're *really*
>> serious about more cranking power, put 2 twelve volts in parallel. You
>> still end up with 12 volts, but the amperage will be doubled. Just make
>> sure the batteries are identical for proper charging.
>
>Wayne:
>
>This is an invitation for disaster! I agree with you, that as long as both
>batteries are identical, everything is OK, and you have twice the charging
>current. But what happens when one battery goes bad (and sooner or later, one
>will)? The good battery will now act as a battery charger to the bad battery.
>With nothing but the internal resistance of the battery to limit current,
>there is a real probability of a melt down.
>
>As for the use of parallel batteries in trucks, are you sure they don't use
>some type of isolation scheme, such as the use of rectifiers, to prevent
>this? I would be interested in learning more about this.
>
>Dan Masters,
>Alcoa, TN
>
>'71 TR6---------3000mile/year driver, fully restored
>'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
> http://www.sky.net/~boballen/mg/Masters/
>'74 MGBGT---3000mile/year driver, original condition
>'68 MGBGT---organ donor for the '74
>
As far as I know, it is safe to connect lead acid batteries of the same voltage
in parallel, and it is common practice. They don't even have to have the exact
same amp-hr rating. Every time you jumper a car battery you're connecting two
batteries in parallel. Now nicad batteries are a different matter, never connect
nicads in parallel.
Bob Donahue, Still Stuck in the '50s
rdonahue@holli.com
52 MG-TD #17639 under DIY restoration, NEMGTR #11470
71 MGB still in shop, 19 months and counting
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