Methods for discharging batteries at DVinfo.net

James Emory · December 28th, 2004, 12:09 AM

What other devices could I safely use to discharge and cycle my Canon batteries when they have not been used for a while with full or partial charges? Could a battery be damaged if I connected a device with bare wires to the terminals if the device required more power than the battery provides? Or would the battery be discharged that much quicker? I know that these are Lithium Ion cells that don't create a memory and can be charged at any time but I just don't like them sitting so long sometimes without a load on them.

For example, if I connected a 12v tube worklight to one of these 7.2v batteries could it damage the battery?

Rob Lohman · December 29th, 2004, 07:43 AM

You are saying you don't want them sitting so long without a load
and you then talk about discharging? Bit confused.

Personally I would not mess with the battery system. You can
always get a good and cheap(er) brand like Lenmar for some
extra batteries or if your main one where to break down (never
had a problem here in 3 years).

A. J. deLange · December 29th, 2004, 01:03 PM

You might try a VL-10Li on camera light which is operated by 900 series batteries. It's pretty useless as a light but it does discharge its battery!

Charles Papert · December 29th, 2004, 01:30 PM

I believe that Li-on batteries do not have an issue with slow discharge over time. You are likely to damage them more by trying to discharge them with a "dumb" device (as opposed to a charger with a discharge mode).

James Emory · December 29th, 2004, 01:39 PM

Rob. I mean that if I don't use them for a while I would like to cycle them and then recharge them but I definitely wouldn't want to use a camera to do it. Then repeat that procedure if they are not used again in that same amount of time.

For example: I would like to fully discharge them at least once every two weeks instead of allowing them to sit with a charge or partial charge until their used again. Canon says to always fully charge shortly before use even if the above has occured no matter what the current charge maybe. As it is known Li-on cells are designed for this but I would rather cycle them if I could. Sometimes I use batteries on a static camera shoot where there is AC power just to be able to cycle them.

I have about 250.00 of useless NiCad and Lead Acid batteries lying around because of this problem of too much time between use. It's just nauseating. Four of them are Lenmar bricks with very low tolerances for not systematically discharging and recharging. I guess if a burglar breaks in I could use them as weapons. But then I could be possibly be charged with assualt and battery.

David Kennett · December 29th, 2004, 02:22 PM

James,

From all I've read aboit Li-ions, completely discharging them will ruin them. Same is true for over-charging. The best state to store Li-ions is partially charged.

December 28th, 2004, 12:09 AM	#1
James Emory Regular Crew Join Date: Aug 2002 Location: Atlanta, Georgia Posts: 1,892	Methods for discharging batteries What other devices could I safely use to discharge and cycle my Canon batteries when they have not been used for a while with full or partial charges? Could a battery be damaged if I connected a device with bare wires to the terminals if the device required more power than the battery provides? Or would the battery be discharged that much quicker? I know that these are Lithium Ion cells that don't create a memory and can be charged at any time but I just don't like them sitting so long sometimes without a load on them. For example, if I connected a 12v tube worklight to one of these 7.2v batteries could it damage the battery?

December 29th, 2004, 07:43 AM	#2
Rob Lohman RED Code Chef Join Date: Oct 2001 Location: Holland Posts: 12,514	You are saying you don't want them sitting so long without a load and you then talk about discharging? Bit confused. Personally I would not mess with the battery system. You can always get a good and cheap(er) brand like Lenmar for some extra batteries or if your main one where to break down (never had a problem here in 3 years). __________________ Rob Lohman, visuar@iname.com DV Info Wrangler & RED Code Chef Join the DV Challenge \| Lady X Search DVinfo.net for quick answers \| Buy from the best: DVinfo.net sponsors

December 29th, 2004, 01:30 PM	#4
Charles Papert Wrangler Join Date: Jan 2002 Location: Los Angeles, CA Posts: 6,810	I believe that Li-on batteries do not have an issue with slow discharge over time. You are likely to damage them more by trying to discharge them with a "dumb" device (as opposed to a charger with a discharge mode). __________________ Charles Papert www.charlespapert.com

December 29th, 2004, 02:22 PM	#6
David Kennett Major Player Join Date: Jul 2003 Location: North Ridgeville, Ohio Posts: 407	James, From all I've read aboit Li-ions, completely discharging them will ruin them. Same is true for over-charging. The best state to store Li-ions is partially charged. __________________ Dave

December 29th, 2004, 01:03 PM	#3
A. J. deLange Major Player Join Date: Jun 2004 Location: McLean, VA United States Posts: 749	You might try a VL-10Li on camera light which is operated by 900 series batteries. It's pretty useless as a light but it does discharge its battery!

December 29th, 2004, 01:39 PM	#5
James Emory Regular Crew Join Date: Aug 2002 Location: Atlanta, Georgia Posts: 1,892	Rob. I mean that if I don't use them for a while I would like to cycle them and then recharge them but I definitely wouldn't want to use a camera to do it. Then repeat that procedure if they are not used again in that same amount of time. For example: I would like to fully discharge them at least once every two weeks instead of allowing them to sit with a charge or partial charge until their used again. Canon says to always fully charge shortly before use even if the above has occured no matter what the current charge maybe. As it is known Li-on cells are designed for this but I would rather cycle them if I could. Sometimes I use batteries on a static camera shoot where there is AC power just to be able to cycle them. I have about 250.00 of useless NiCad and Lead Acid batteries lying around because of this problem of too much time between use. It's just nauseating. Four of them are Lenmar bricks with very low tolerances for not systematically discharging and recharging. I guess if a burglar breaks in I could use them as weapons. But then I could be possibly be charged with assualt and battery.