T-Pain Is On A Boat: Re: [Electric Boats] An electric cruise to and from New York and a battery question.

Wednesday, September 23, 2009

Re: [Electric Boats] An electric cruise to and from New York and a battery question.

Mike,

It depends on the charge voltage of your Zivan. If any one battery goes above 14.4 volts (check your particular manufacturers recommendation) during the charging process, dehydration is possible. If any battery goes above 14.6 volts, dehydration is extremely likely. Once an AGM dehydrates, you'd have to be a surgeon to rehydrate it.

AGMs don't have a drop of moisture to spare.

The beauty of the Paktraker: it records peak voltage, right?

Another trick: alligator clip a small load (5W light bulb?) across the highest voltage battery during the charging process. Reset Paktraker, then check for peak voltages after your next charging cycle.

A fancier automated version is to install a high voltage trigger circuit on each battery that turns on a light once the battery reaches your preset voltage level, then turns it off after the voltage drops below the trigger.

The idea behind these "light" methods: it discourages runaway voltage battery greediness (lead acid batteries have a natural relationship between voltage and resistance: the higher the voltage, the less resistance to charging).

Enjoy,
Mark Stafford
Frantically installing e-motor so the Berkeley Marina won't kick me out. Well, I need a haul-out anyway. Any 60' sailboat haul-out y'all could recommend around the SF Bay?

--- In electricboats@yahoogroups.com, Mike <biankablog@...> wrote:
>
> Mark:
>
> Thanks Interesting info. Especially about the AGM high voltage issue. I do have one battery (AGMs)in the bank (the most positve one) that consistantly seems a little higher (some times .5 volts higher than the lowest) in voltage than the other three when charging. Of course this was the case before this incident too. I have a Paktraker installed so it's easy to keep an eye on all the voltages. So it looks like this is the is the battery I should be most concerned about.
>
> Mike
> http://biankablog/blogspot.com
>
>