GEL and AGM batteries

[KP44]

Just sayin' ….
I had two 8D AGMs from West Marine. These are supposed to be maintenance-free and you can even set them on their side because they will never leak or have problems.
Two of the 8D batteries had cracks that were visable and acid had leaked out. The batteries had never been abused, dropped, or battered. They had been discharged and then charged and used again, but that is the extent of any rough treatment.

[john61ct]

And the lesson was?

Besides buy better quality batteries?

That this is false

Originally Posted by KP44

because they will never leak or have problems.

Also, make sure they're completely secured, fixed in place no movement, even if the boat flips, no stresses nor strains on wires nor terminals.

[surazo]

Hi KP44 , attached link to samlex

https://samlexamerica.com/documents/...513%20Lrez.pdf

Reading carefully the manual i have a serious doubt if it's possible set the banks individually or only is selectable one type of battery for the charger.
What do you think?
Regards Hernan

[john61ct]

Yes that puts the same voltage on all three outputs, as do most.

Just means you don't need VSRs between the banks, if that is your only charge source.

For different outputs, need Sterling B2B

and/or this add-on

https://www.google.com/search?q=ster...q=sterling+bcm

[surazo]

Thanks john61ct . I think that you are right .I'm going to investigate the link mentioned and try to understand if a Battery link ACR PN7600 could be useful to fit in the charging cables .This device is a gift never used and it seems that could be set the overvoltage and undervoltage for a range of charging compatible with gel batt .
Indeed the sterling is the final solution for different charge profiles

[john61ct]

Originally Posted by surazo

try to understand if a Battery link ACR PN7600 could be useful to fit in the charging cables

Limited to I believe 60A

a feature I prize highly, whenever one comes up on eBay for under $40 I grab it, very hard to source now it's been many years since they were discontinued.

[john61ct]

Since the GEL wants lower voltage and doesn't want high current, check out Echo Charger, and the charge specs for your GEL.

Limits current to 15A and has a bit of voltage drop, max voltage is 14.4v.

Most consider these flaws but in this case may be perfect for you.

[a64pilot]

Isn’t the Gel connected to other batteries as part of a bank?
If so then you can’t charge it independently, to do that would mean that it’s it’s own isolated bank.
You could do that of course and recombine etc, but it’s certainly not worth that.
It’s going to die an early death, but I don’t think it’s going to fail in any kind of catastrophic manner, and if it’s new, and if the rest of the bank old, it may last as long as the bank?
I believe this falls under the it’s not right, but not worth getting too upset and spending money on to fix it.

[surazo]

Thanks John and A64pilot for your kindly support .During this days I made a post doc in batts .Finally the solution is always the more simple .As suggested don't invest more money and limited the current to gel batt to 14.1 volts ,because any catastrophic event going to happend in the short or medium term.
thanks again

[a64pilot]

Just when you do need to replace the bank, it’s best to do so with identical batteries and if possible the same age.
A bank is like a flashlight full of D cell batteries, thats a bank, and I guess you can argue that only one is bad, so I’ll just replace the bad single battery, but that doesn’t usually work well, the old batteries seem to kill the new one down to their health level pretty quickly.

[surazo]

Indeed is the best but when you have many years sailing and with the time are integrated more electronic equpment and increse the batt capacity , is quite expensive to replace all batts at same time but it going to remain in my mind

[model 10]

[QUOTE=a64pilot;
I believe this falls under the it’s not right, but not worth getting too upset and spending money on to fix it.[/QUOTE]




That was my feeling when I installed a Gel in with 4 agm's. The guy next to me bought 8 new AGM 's for his boat, all at one time. There is never going to be a time when I can do something like that again. I did that once and had several fail a 1000 miles from home. Now I pay attention to batt temp and use an old batt load tester to see how they are doing.