Lipo Battery Storage %?

[ChrisCapaldi]

I just used my Hyperion EOSO606i AC/DC charger to charge my 6400mah 3C Lipo starter battery to store it for the winter. I used the charger's storage mode functionality on the battery and it completed it's process normally.

Just out of curiosity, I used my Lipo battery checker to see what % the charger set the battery to. It is registering 15% for all 3 cells. The % is not something I see that I can set in the charger's settings. 15% is lower than I expected...what % are your chargers charging the batteries to for storage?
Thanks,
Chris

 

[longballlumber]

Chris,

The default factory setting on all of my Hyperion chargers has been 60% for storage mode.

 

[RaceMechaniX]

I recommend storage around 3.7V/cell. If the cells are between 3.5-3.85V and well balanced I will leave them alone. If they are above or below that range or have move than 50mV imbalance I will put them on a storage charge with slow balance.

 

[ChrisCapaldi]

Each of the 3 cells are at 3.73V and 15%. The charger took a couple of hours to complete it's storage cycle whereas a charge cycle is much quicker.
Thanks,
Chris

 

[ChrisCapaldi]

Hi Mike, 60% is around what I was thinking it would set the battery to as well. The 15% it set it to is lower than I expected.
Chris

 

[Wasted wages]

Is the storage % adjustable within the charger setup parameters?

 

[ChrisCapaldi]

Hi Frank, I just checked and if it is, it's not obvious...I'm going to keep looking though as maybe it's hidden somewhere.
Chris

 

[ChrisCapaldi]

It looks like it's not a setting that I can change. The manual says it should be finishing up around 60% so I'm not sure why mine is complete at 15%.
Chris

 

[Wasted wages]

Maybe check with Hyperion ??

 

[longballlumber]

I recommend storage around 3.7V/cell. If the cells are between 3.5-3.85V and well balanced I will leave them alone. If they are above or below that range or have move than 50mV imbalance I will put them on a storage charge with slow balance.

I am missing something Tyler. 3.7v/cell in a lipo would be 15%-30%. Are you really storing your that low?

 

[longballlumber]

Each of the 3 cells are at 3.73V and 15%. The charger took a couple of hours to complete it's storage cycle whereas a charge cycle is much quicker.
Thanks,
Chris

If it took a couple of hours for the charger to complete the storage cycle, there is something not right. Either with the battery or with the charger. Unless the charge rate is really low OR the battery was near full charge and the charger had to discharge the battery.

If the charger put the battery at 60% capacity for storage you should be at or around 3.87v/cell or 11.62v for a 3S pack. Just to confirm this is a LiPo pack right?


https://blog.ampow.com/lipo-voltage-chart/

 

[Daniel's Racing]

The green is recommended storage at 3.80 volt per cell

 

[ChrisCapaldi]

Yes, This is a 3C Lipo pack. It is showing as 3.73V right now after the store mode completed. That lines up with the chart so it looks like my battery checker is working ok. I think I'm going to give the pack a charge and try to cut it off short so it's around 60%. It looks like that is where it really should be at and not 15% like it is now.
Thanks for all the help guys! This is why IW is such a great group. So much knowledge!
Chris

 

[Bob Zola]

Shoot for 3.85v per cell. When I was a battery dealer, that's the voltage I received the packs in at most of the time (from the manufacturer). The factory called this ideal storage level.

 

[Martin Hamilton]

I always store at 3.82v - 3.84v or 45% - 50%.

 

[RaceMechaniX]

I am missing something Tyler. 3.7v/cell in a lipo would be 15%-30%. Are you really storing your that low?

Yeah, I store mine usually 3.5-3.7V/cell. Less energy in the cells in case something were to happen while in their flammables locker and at least from my monitoring checks the batteries tend to be self discharge less when at a lower resting voltage. I check all my packs (about 40 of them) every month looking for dropouts or high imbalance.

 

[pilothyer]

I agree with Daniel's Racing, Bob Zola and Martin Hamilton. All my chargers, Hyperion, Hitec, Thunderpower, and Spektrum, charge or discharge to 3.85 volts per cell when storage mode is selected. All my batteries are used mostly for air and some surface and I generally try to end my flights so the recovery voltage is close to storage voltage. That way at the end of the day bringing them to storage voltage take very little time.

 

[Daniel's Racing]

Shoot for 3.85v per cell. When I was a battery dealer, that's the voltage I received the packs in at most of the time (from the manufacturer). The factory called this ideal storage level.

New shipping regulations has forced most manufactures to ship at 30% or less.

So this as received voltage is no longer any relation to what is best for the pack though. It is best for safety. They suggest charging to proper voltage upon receipt.

But yes sir 3.80 to 3.85 is a fine per cell voltage to store Lithium Polymer packs.

 

[John Callahan]

Daniel, thanks for the lipo chart. Is there a chart like that for our LiFe packs? Thanks.

 

[Daniel's Racing]

Daniel, thanks for the lipo chart. Is there a chart like that for our LiFe packs? Thanks.

They prefer 60-75% capacity. So full charge then remove 25% . It is roughly 3.2-3.25 volt but you can not really use voltage for much of anything related to capacity on a LiFe battery.

The voltage is so loosely related to the capacity it means little. Lifes lose a little at the top from 100% to 90% capacity then they may not barely loose a tenth(.10 volt) of a volt from 90% to 10% capacity.

This is why volt meters are pretty worthless on a LiFe powered receiver system. You can only go by capacity taken away. If you know the draw times the ON time but you can't determine that except if you had a watt meter in the boat.

Charge them and use them right away then store them. Charge before you go again is one simple way. Not perfect though.

You fully charge so you get familiar with what your replacing if you always go out full you can see what the charger put back in the pack and know what you used.

Best is to take home fully charge then remove 25% capacity in mah with a dischage cycle. One trick I use is set the discharge for one more cell than you have and it will stop it in a safe zone. 2S just set a 3S discharge. Confirm what your charger pulls out of course. .