SEC AGM Batteries

[Plevier]

Not used Odysseys, but Nigel Calder seems to be having problems with the capacity holding up on his TPPLs for his all-electric boat. Merlin/Powerstore swear by them for starter/bowthruster work and it took three weeks to break one when they were testing them.

Makes sense on both counts.
Are there up to date progress reports available somewhere? The Hymar website doesn't really tell you that. The funded project is supposed to complete this year isn't it?

 

[sailinglegend420]

Makes sense on both counts.
Are there up to date progress reports available somewhere? The Hymar website doesn't really tell you that. The funded project is supposed to complete this year isn't it?

Go to this forum: http://www.cruisersforum.com/forums/f14/odyssey-tppl-batteries-85767.html

I quote the first posting of 21/07/2012:

"An interesting piece in this month's Sail magazine by Nigel Calder about his ongoing experiences with the Odyssey batteries. He is finding that they are losing capacity over time although it seems different from normal sulfation. He cut one open and didn't find the normal white crystals of sulfation. They looked perfect.

In any case, he has been experimenting with equalizing them and says the missing capacity returns. He is using really high voltages. Charging at 3-5 amps at 17 volts into a 100 amp hour battery for three hours. He saw no case bulging, excess heat or blown caps.

He's also concluded that these batteries should have much longer acceptance charges at 14.8V. Four to eight hours normally and an occasional 16-20 hours of acceptance voltage when plugged in to a dock.

This all seems pretty radical. Anyone have an opinion?

Carl"

EDIT:

Article found here:
http://mydigimag.rrd.com/display_article.php?id=1117481

 

[Plevier]

Article found here:
http://mydigimag.rrd.com/display_article.php?id=1117481

Thank you. Interesting but not a new discovery!
We were seeing similar capacity loss behaviour unpredictably in our TPPL AGM batteries in the late 80s and finding that very high voltages - sometimes a lot more than 17V - could sometimes bring partial recovery but probably at the expense of life. They did gas, you could hear them.
We saw the same but less marked in our thick plate lead calcium AGMs. We did establish it was very important to recharge immediately but I don't recall a linkage with the rate of charge for which we specified a min of C/10 and a max of C.
I see that for Odyssey they are now stressing the need for high rate charging, same as Lifeline do.