Reviving AGM batts - DIY Electric Car Forums
Go Back  

DIY Electric Car Forums > EV Conversions and Builds > Batteries and Charging

Register Blogs FAQ Members List Social Groups Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Display Modes
  #1  
Old 08-12-2008, 01:12 PM
grose grose is offline
Member
 
Join Date: Apr 2008
Location: Clintonville, WI
Posts: 63
grose is on a distinguished road
Default Reviving AGM batts

I have two 12V, 110AH AGM batteries that have lost a substantial portion of their capacity. Is there any way to revive these or should I get new ones?
Reply With Quote
Sponsored Links
Advertisement
 
  #2  
Old 08-12-2008, 01:52 PM
TheSGC TheSGC is offline
Senior Member
 
Join Date: Nov 2007
Location: Massachusetts
Posts: 1,553
TheSGC is on a distinguished road
Default Re: Reviving AGM batts

Quote:
Originally Posted by grose View Post
I have two 12V, 110AH AGM batteries that have lost a substantial portion of their capacity. Is there any way to revive these or should I get new ones?
What are you using for a charger and how old are the batteries?
__________________
2001 Civic EX EV
http://2001-civic-ev.blogspot.com
EV's are never done, they just reach a point where you can drive them.
Reply With Quote
  #3  
Old 08-12-2008, 02:05 PM
grose grose is offline
Member
 
Join Date: Apr 2008
Location: Clintonville, WI
Posts: 63
grose is on a distinguished road
Default Re: Reviving AGM batts

Quote:
Originally Posted by TheSGC View Post
What are you using for a charger and how old are the batteries?
Charger is a Schumacher 12V 6A smart charger. The batteries are a year old and have 1600 EV miles on them.
Reply With Quote
  #4  
Old 08-12-2008, 11:12 PM
rebenergy rebenergy is offline
Member
 
Join Date: Apr 2008
Location: Yankton South Dakota
Posts: 63
rebenergy is on a distinguished road
Default Re: Reviving AGM batts

Hi grose
My advice is just off the cuff and I am leaving for vacation, so I can’t provide any links to support my statements at this time. A Schumacher 12V 6A smart charger may not provide enough current to equalize the batteries. (Equalizing is the causing of bubbles to move by plates mixing electrolyte and chafing the lead sulfate crystals off the plates). If the batteries are sulfated a few good equalizing charges may help. You could then follow this process by topping off the electrolyte by adding standard battery acid, NOT distilled water. This will not damage old batteries, but gives them a second wind. If you have the time you could buy a high frequency desulfatetor. I have heard good reviews, but have not yet used one my self. I do not believe in using cleiagents (sorry bad spelling) like EDTA. They encapsulate the lead-sulfate crystal sloughing so much sludge to the bottom of the plates and sorting them out.

Here is a clip of an old advertisement --

PulseTech® battery maintenance systems clean the
working parts of your battery...and here’s the
VISIBLE PROOF!
These are crystallized sulfur
molecules on a typical lead-acid
battery plate. These “sulfates”
reduce your battery’s capacity,
shorten its lifetime, and interfere
with energy efficiency... bad news for
your battery.
Here’s the same plate 18 days later,
after installing a PulseTech® battery
maintenance system. The plates are
clean. This battery’s storage capacity
increased 250%, without the use of
costly equalization charging... good
news for your bottom line.
Extend the Life of your Batteries!
Accept no substitutes; the cost
effective PowerPulse® units
are patented, approved by the
U.S. Military, and have a tenyear
limited warranty.
n Free delivery to 50 States. n VISA/MasterCard OK!
n Bulk/Dealer inquiries invited.
Reply With Quote
  #5  
Old 08-12-2008, 11:41 PM
ww321q's Avatar
ww321q ww321q is offline
Senior Member
 
Join Date: Mar 2008
Location: Merced , Ca.
Posts: 574
ww321q is on a distinguished road
Send a message via Yahoo to ww321q
Cool Re: Reviving AGM batts

I have had some luck desulfating regular lead acid and gel cells . How come just 2 batteries ? I'm sure your string is longer ? They could be dried out from high discharge or to high voltage when charging . there are desulfaters that you can build to . The Schumacher chargers I have , have one built in . I also have another I bought .

[top]BLS-12/24B



http://www.batterylifesaver.com/products/products.htm
hope this helps J.W.
Reply With Quote
  #6  
Old 08-13-2008, 09:15 AM
TX_Dj's Avatar
TX_Dj TX_Dj is offline
SPAM Cop
 
Join Date: Jul 2008
Location: Texas, Plano (Dallas)
Posts: 1,499
TX_Dj is on a distinguished road
Default Re: Reviving AGM batts

Quote:
Originally Posted by rebenergy View Post
You could then follow this process by topping off the electrolyte by adding standard battery acid, NOT distilled water.
I don't see how this is a possible suggestion with sealed AGM batteries.
__________________
cheers,
dj
"I'm No Expert!(TM)"
A fuel and his money are soon parted...
Reply With Quote
  #7  
Old 08-13-2008, 10:02 AM
grose grose is offline
Member
 
Join Date: Apr 2008
Location: Clintonville, WI
Posts: 63
grose is on a distinguished road
Default Re: Reviving AGM batts

Quote:
Originally Posted by ww321q View Post
I have had some luck desulfating regular lead acid and gel cells . How come just 2 batteries ? I'm sure your string is longer ? They could be dried out from high discharge or to high voltage when charging . there are desulfaters that you can build to . The Schumacher chargers I have , have one built in . I also have another I bought .

[top]BLS-12/24B



http://www.batterylifesaver.com/products/products.htm
hope this helps J.W.
Just two batteries are showing this weakness in the string. The others load test better. How successful are these desulfaters? Are there any verified results that they work? (other than anecdotal)
Reply With Quote
  #8  
Old 08-13-2008, 10:12 AM
adric22 adric22 is offline
Member
 
Join Date: Jan 2008
Location: Kennedale, TX
Posts: 64
adric22 is on a distinguished road
Default Re: Reviving AGM batts

Quote:
Originally Posted by TX_Dj View Post
I don't see how this is a possible suggestion with sealed AGM batteries.
You took the words right out of my mouth. I was about to mention the same thing. Not only can you not add acid to an AGM, but I don't believe you want any bubbles forming in there. Bubbles are very bad for AGMs.
__________________
David Murray
Electric 1993 Eagle Talon
http://galaxy22.dyndns.org/ev-talon
Reply With Quote
  #9  
Old 08-13-2008, 12:17 PM
judebert's Avatar
judebert judebert is offline
Senior Member
 
Join Date: Apr 2008
Posts: 220
judebert is on a distinguished road
Default Re: Reviving AGM batts

Quote:
Originally Posted by adric22 View Post
You took the words right out of my mouth. I was about to mention the same thing. Not only can you not add acid to an AGM, but I don't believe you want any bubbles forming in there. Bubbles are very bad for AGMs.
On the EVDL, none other than Lee Hart himself suggests that some AGMs can be saved by drilling a small hole (7/64", I believe), adding the fluid, and sealing the hole with silicon and a #7 screw.
Reply With Quote
  #10  
Old 08-13-2008, 12:40 PM
TX_Dj's Avatar
TX_Dj TX_Dj is offline
SPAM Cop
 
Join Date: Jul 2008
Location: Texas, Plano (Dallas)
Posts: 1,499
TX_Dj is on a distinguished road
Default Re: Reviving AGM batts

It certainly doesn't surprise me that Lee would do something like that. And if he has, and was successful, I would trust his data on the subject... question is, does anyone have a link to his findings?
__________________
cheers,
dj
"I'm No Expert!(TM)"
A fuel and his money are soon parted...
Reply With Quote
Reply

Share or Bookmark this

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

 
Support DIY Electric Car
Sponsors

All times are GMT -6. The time now is 09:27 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.

Ad Management by RedTyger