LIPO storage mode question
#1
Thread Starter
Tech Regular
Joined: Sep 2009
Posts: 353
When setting my charger to put my lipos in storage do I set the amp setting the same as if I am charging them? I could not find the info in my manual. Thanks.
Also, how close are your cells in voltage after a typical run? Is there a certain range I should watch for?
Also, how close are your cells in voltage after a typical run? Is there a certain range I should watch for?
#2
Tech Master
iTrader: (3)
Joined: Jul 2008
Posts: 1,465
From: Melbourne, Australia
What charger do you own ?
Different chargers approach storage mode differently
The aim is to get the pack to around 50% or 3.85v / cell, anywhere between 3.7 and 3.9 will be fine
Some chargers will only discharge from a higher voltage 'down' to storage voltage (Discharge rate will be limited to the discharge rating of the charger, small 50 watt chargers usually rate limit the discharge rate to 5 watts or so)
Usually discharge does not include balancing
Some chargers will only charge 'up' to storage voltage using the normal settings for charging, may include balancing
Some chargers will automatically charge or discharge based on voltage
Cheers
Different chargers approach storage mode differently
The aim is to get the pack to around 50% or 3.85v / cell, anywhere between 3.7 and 3.9 will be fine
Some chargers will only discharge from a higher voltage 'down' to storage voltage (Discharge rate will be limited to the discharge rating of the charger, small 50 watt chargers usually rate limit the discharge rate to 5 watts or so)
Usually discharge does not include balancing
Some chargers will only charge 'up' to storage voltage using the normal settings for charging, may include balancing
Some chargers will automatically charge or discharge based on voltage
Cheers
#3
Thread Starter
Tech Regular
Joined: Sep 2009
Posts: 353
I have a Thunder AC6 charger and run 4000mah 25C lipos. When I put it in storage mode it requires I put in a charge rate and I am wondering if I should set that to the same rate as when I am doing a normal charge.
#4
R/C Tech Elite Member
Joined: Oct 2006
Posts: 1,583
Storage: If you do not plan to use your lipo pack for longer than a week, store it at 50-60% of the pack’s rated capacity. Make sure to cycle and/or balance your packs at least once per month since leaving them on the shelf for a prolonged period can cause the packs to get severely out of balance or even go dead.
#5
Joined: Jul 2008
Posts: 11,530
From: Houston, TX
I wouldn't use the same rate as you do for charging, use a small charge/disch rate like 1amp for both. You don't want a high charge/disch rate. You want a low charge/disch rate so the voltage comes down slowly and evenly to the storage value and shows littel voltage recovery after the charger stops. This will help with cell balance too.
As far as cell diff goes, the better quality cells usually show less than 5mv - my Neuenergys are like this. My Turnigys show 10-15mv diff in individual cell voltages. So it depends on the lipo a littel as to what you should expect. Just observe yours and see what they are like. It'll prob stay that way until they get close to needing replacement.
#7
Joined: Jul 2008
Posts: 11,530
From: Houston, TX
My manual says 0.7amps, not volts.
This is due to the charger's discharge wattage limitation of 5watts. You could set it higher, but this is all the charger can do. I forgot about the discharge being limited.
Don't discharge a lipo to that low of a voltage, it'd be damaged and swell up like a little football.
This is due to the charger's discharge wattage limitation of 5watts. You could set it higher, but this is all the charger can do. I forgot about the discharge being limited.
Don't discharge a lipo to that low of a voltage, it'd be damaged and swell up like a little football.
#8
My manual says 0.7amps, not volts.
This is due to the charger's discharge wattage limitation of 5watts. You could set it higher, but this is all the charger can do. I forgot about the discharge being limited.
Don't discharge a lipo to that low of a voltage, it'd be damaged and swell up like a little football.
This is due to the charger's discharge wattage limitation of 5watts. You could set it higher, but this is all the charger can do. I forgot about the discharge being limited.
Don't discharge a lipo to that low of a voltage, it'd be damaged and swell up like a little football.
#10
Thread Starter
Tech Regular
Joined: Sep 2009
Posts: 353
Thank you for all the replies. I found out after playing with my charger yesterday that it has a maximum setting of 1 amp for storage mode, but I never saw it go above 0.6 amps while the battery was hooked up. I don't know how low it takes the batteries for storage mode as I had to pack up when the battery was at 7.92 volts.
If I run the battery and it is at say 7.6 volts when I put it on the charger can I just charge it normally until it reaches 7.8 volts and then pull it off the charger and store it?
If I run the battery and it is at say 7.6 volts when I put it on the charger can I just charge it normally until it reaches 7.8 volts and then pull it off the charger and store it?
#11
Joined: Jul 2008
Posts: 11,530
From: Houston, TX
Its still a little high at 7.92v (3.96v/cell), so it needs a little more time on disch. The current limit your runing into is the 5watts max discharge allowed by the charger. 5watts/7.92v =.63amps so you're limited to 0.6a.
If you run the lipo to a resting voltage of 7.6v, you've basically placed it in storage, that's 3.8v/cell and its close enough. 3.85v/cell is just the average for the recommended storage range which is 3.78V~3.92v/cell.
If you run the lipo to a resting voltage of 7.6v, you've basically placed it in storage, that's 3.8v/cell and its close enough. 3.85v/cell is just the average for the recommended storage range which is 3.78V~3.92v/cell.
#12
Joined: Jul 2008
Posts: 11,530
From: Houston, TX
Storing at full 4.2v/cell charge for long periods is supposed to increase internal resistance, which is going to affect C rating (decrease it). There is some form or kind of cumulative damage from sitting fully charged for long periods. I've seen well cared for lipos puff and they had always been kept fully charged.




