robert nanzig wrote:
snip,
Should I be patient and give the battery time to
> recharge or should 15 minutes of driving be enough time for the ammeter
> to work it's way back to zero. This stuff mystifies me.
>
> Rob Nanzig
> 67SV
If it were me I would be patient and drive a bit longer before worrying.
A car battery is capable of storing quite a bit of energy. Let's say you have a 50
amp-hr rated battery. This should be capable of delivering, say, 50 amps for 1 hour,
better yet, lets restate it as 5 amps for 10 hours. Lets also say that the battery
had been drained to a 50% state of charge. This would mean that you had to replenish
25 amp hours of energy. Assuming 100% charge effieiciency (it is not), you could
charge the battery for 25 amps for one hour and fully recharge the battery. (In
actual practice the battery charge characteristics are more complicated, but you get
the idea). Or charge it at 12.5 amps for 2 hours. So, as you say, it was chargng at
15 to 25 amps for 15 minutes and still charging hard. This, by itself, is not a
concern.
It all depends on the battery capacity and the battery state of charge (ie:
discharge) when you re-hooked up the alternator.
Oh yeah, if it were me I would place a battery charger on the battery and let it run
for a few hours. Monitor the current going into the battery, when it starts to taper
down you know that you are approaching a fully charged battery and when it is small
(maybe 1/2 amp) you have an essentially fully charged battery.
Now if you have a fully charged battery and the current meter indicates that you
continue to drive excess current into the battery then you do have a problem. This
will shorten the life of the battery, maybe dramatically.
-Roger
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