R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 10-01-2003, 08:39 PM   #1
Regional Moderator
 
disaster999's Avatar
 
Join Date: Aug 2001
Location: Hong Kong
Posts: 3,182
Trader Rating: 1 (100%+)
Default Dying SMC battery

got a pack of matched smc battery for about...1.5 years old, at first it charged out fine 3-4 months ago, but recently, the cell seems to die on me! the peak volt of the pack was around 10 volts and only have about 2500mah in it!

anyway i could revive it? or its a goner?
disaster999 is offline   Reply With Quote
Old 10-01-2003, 09:14 PM   #2
Tech Prophet
 
Randy Caster's Avatar
R/C Tech Elite Subscriber
 
Join Date: Mar 2003
Location: Costa Mesa, CA
Posts: 16,675
Trader Rating: 46 (100%+)
Default

Try discharging it as low as it will go, then dead short each cell individually. Should erase any memory that the pack has, and may work to revive it.
Randy Caster is offline   Reply With Quote
Old 10-01-2003, 09:27 PM   #3
Regional Moderator
 
disaster999's Avatar
 
Join Date: Aug 2001
Location: Hong Kong
Posts: 3,182
Trader Rating: 1 (100%+)
Default

Quote:
Originally posted by Randman
Try discharging it as low as it will go, then dead short each cell individually. Should erase any memory that the pack has, and may work to revive it.
oops i forgot to mention that its 3000mah batt...not nicd!
disaster999 is offline   Reply With Quote
Old 10-01-2003, 09:36 PM   #4
Tech Prophet
 
Randy Caster's Avatar
R/C Tech Elite Subscriber
 
Join Date: Mar 2003
Location: Costa Mesa, CA
Posts: 16,675
Trader Rating: 46 (100%+)
Default

Not sure in that case, that worked for me with NiCD batts, never tried it on a NiMH, but I guess it couldn't hurt the cell anymore than it already is.
Randy Caster is offline   Reply With Quote
Old 10-01-2003, 09:50 PM   #5
Tech Regular
 
boner's Avatar
 
Join Date: Oct 2001
Posts: 343
Trader Rating: 3 (100%+)
Default

what kind of 3000? GP or SANYO? your cells are old. just use what you brought over from your home.
boner is offline   Reply With Quote
Old 10-01-2003, 10:20 PM   #6
Tag
Tech Master
 
Tag's Avatar
 
Join Date: Sep 2001
Location: Arcadia CA
Posts: 1,589
Trader Rating: 31 (100%+)
Default

i know dead shorting is commonly used for nicad but i had tried with a dying gp3300 with good result. I have a set of dying 3300 , peak around 10V and only about 2800 mah when fully charged. Just like Ranman suggested, discharge the pack and put them on a tray for a few days ( deadshorting the batt individually) , followed this method i was able to bring back my old 3300 to peak about 9.3+- and had about 3100-3200 in the batt..
__________________
* Serpent 966 TE Novarossi 35+21, Airtronics M12 *
Tag is offline   Reply With Quote
Old 10-01-2003, 10:54 PM   #7
Tech Elite
 
lee82gx's Avatar
 
Join Date: Nov 2002
Location: Land Of peace , Malaysia
Posts: 2,304
Trader Rating: 1 (100%+)
Default

Tag:
forgive the obvious ignorance but i wanted to be sure:
Were u suggesting the Nicad(dead shorting 0V) tray or 1.2V-cut off try?
how long did the revive last?
lee82gx is offline   Reply With Quote
Old 10-01-2003, 11:02 PM   #8
Tech Prophet
 
Randy Caster's Avatar
R/C Tech Elite Subscriber
 
Join Date: Mar 2003
Location: Costa Mesa, CA
Posts: 16,675
Trader Rating: 46 (100%+)
Default

I saved the money on a discharge tray, and just soldered a wire from the positive to negitive terminal on the battery
Randy Caster is offline   Reply With Quote
Old 10-01-2003, 11:17 PM   #9
Tech Elite
 
lee82gx's Avatar
 
Join Date: Nov 2002
Location: Land Of peace , Malaysia
Posts: 2,304
Trader Rating: 1 (100%+)
Default

Right,dead short it is.
i have to discharge the cells to 0.9V first right?
lee82gx is offline   Reply With Quote
Old 10-01-2003, 11:18 PM   #10
Tech Prophet
 
Randy Caster's Avatar
R/C Tech Elite Subscriber
 
Join Date: Mar 2003
Location: Costa Mesa, CA
Posts: 16,675
Trader Rating: 46 (100%+)
Default

Whatever the lowest voltage you can get is, discharge it to that, otherwise the cells will get real hot when dead shorting them, and may cause more damage than good.
Randy Caster is offline   Reply With Quote
Old 10-01-2003, 11:24 PM   #11
Tech Elite
 
lee82gx's Avatar
 
Join Date: Nov 2002
Location: Land Of peace , Malaysia
Posts: 2,304
Trader Rating: 1 (100%+)
Default

Ok.thanks.i think i'll parallel a coupla resistors and then discharge it that way
and then put on dead shorting wires.
thanks.
lee82gx is offline   Reply With Quote
Old 10-01-2003, 11:27 PM   #12
Regional Moderator
 
disaster999's Avatar
 
Join Date: Aug 2001
Location: Hong Kong
Posts: 3,182
Trader Rating: 1 (100%+)
Default

ive always been told all my live that its a bad idea to dead short nimh batteries! you guys really sure that its a good idea to dead short nimh?

and just to make things clear here...the pack that is giving me problems is sanyo 3000 matched by smc
disaster999 is offline   Reply With Quote
Old 10-01-2003, 11:28 PM   #13
Tech Prophet
 
Randy Caster's Avatar
R/C Tech Elite Subscriber
 
Join Date: Mar 2003
Location: Costa Mesa, CA
Posts: 16,675
Trader Rating: 46 (100%+)
Default

I've never done NiMH personally, but Tag seemed to have good results...
Randy Caster is offline   Reply With Quote
Old 10-01-2003, 11:32 PM   #14
Regional Moderator
 
disaster999's Avatar
 
Join Date: Aug 2001
Location: Hong Kong
Posts: 3,182
Trader Rating: 1 (100%+)
Default

guess ill wait for more responds and more ppl to agree with Tag then
disaster999 is offline   Reply With Quote
Old 10-01-2003, 11:35 PM   #15
Tech Elite
 
lee82gx's Avatar
 
Join Date: Nov 2002
Location: Land Of peace , Malaysia
Posts: 2,304
Trader Rating: 1 (100%+)
Default

i wouldnt do it to new cells,but for those dilapidated ones i wouldnt mind trying just for the heck of it.
doesnt really require a lot of money too.
another thing:
it might be a good idea to zap ur old sanyo's disaster999.
lee82gx is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
i'm dying for this mustang speedchannel Web Links 4 08-12-2008 06:10 PM
Dying wheels jrwoodchuck Nitro Off-Road 3 07-27-2008 04:53 PM
Dying to buy another car......... rc_freak R/C Items: Wanted to Buy 23 10-27-2007 09:20 PM
dying????? im faster Nitro On-Road 1 03-05-2007 02:56 AM
Is EP TC racing dying? Edwin Lee Malaysian R/C Racers 221 04-28-2005 12:46 AM



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

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
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 09:59 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net