Lipo battery storage

[Ericehess]

I have a lot of 2S and 3S lipo batteries. Once I run them down til low voltage protector kicks in, is it ok to keep them like this for a week or so until I recharge and use them? I have read it shortens life of battery to not store them at half charge. This is difficult to do sometimes. I have one good charger that can bring them to storage charge but it takes awhile when multiple batteries are in play. Any advice? What do you do with a used battery you dont plan to use for awhile?

 

[tntpoof]

build a bulb discharger with a fan on it.. use a lipo buzzer ...the this is some people say 3.76 or even 3.8 is good to store a battery at thats for 1 cell.. so adding that to make 2 or 3 cells.is 7.6 ish is good for 2 cell now a 3 cell 11.28....A week after bounce back is gonna be what? close to 8?..so id try and take them down alittle more....but a week adds up in a lipos life...store in cool dry area if you can . I have a old steel fridge I keep mine in .some weeks I run 4 batteries 5-6x a week...but I always store mine at storage.. a couple of 1157 12v dc light bulbs knock it down quick.. I have several different ways to discharge a lipo to store them from a old school 25 amp discharger to several reactor dischargers from 5-25 amps all adjusted to run a 2 cell battery down to 3.75 volts a cell so 7.5 and buld dischargers.

 

[Ericehess]

build a bulb discharger with a fan on it.. use a lipo buzzer ...the this is some people say 3.76 or even 3.8 is good to store a battery at thats for 1 cell.. so adding that to make 2 or 3 cells.is 7.6 ish is good for 2 cell now a 3 cell 11.28....A week after bounce back is gonna be what? close to 8?..so id try and take them down alittle more....but a week adds up in a lipos life...store in cool dry area if you can . I have a old steel fridge I keep mine in .some weeks I run 4 batteries 5-6x a week...but I always store mine at storage.. a couple of 1157 12v dc light bulbs knock it down quick.. I have several different ways to discharge a lipo to store them from a old school 25 amp discharger to several reactor dischargers from 5-25 amps all adjusted to run a 2 cell battery down to 3.75 volts a cell so 7.5 and buld dischargers.

I usually dont have a problem with discharging them..can just run a car for a bit if that's the issue..its whether or not it's ok to store them for a week or so fully discharged is my question. I usually bring them up to storage voltage if it's going to be more than a few days without using..but dont always.

 

[tntpoof]

the lvc on most esc dont go below storage charge... so unless you give me a number I'm not going to give you A answer..so figure it out from the numbers I gave already....

 

[Ericehess]

the lvc on most esc dont go below storage charge... so unless you give me a number I'm not going to give you A answer..so figure it out from the numbers I gave already....

I thought storage charge for a 2s was around 7.7v and 11.5v for 3s. The LVC is set to 3.3v, so 6.6v for 2s 9.9v for 3s. So when I run the battery down to 6.6 or 9.9v it is well below proper storage voltage.

 

[tntpoof]

dont store or let stand at those voltages you listed 2 far below storage voltage . damage will happen.. you will lose mah in each cell...

 

[Ericehess]

So 3.3v per cell is is too low for storing? Gotcha..that was my question..do you set your LVC higher than 3.3v?

 

[Racer 1966]

Simple answer is a week or 2 won't cause any issues. Months or years is a different story.

 

[tntpoof]

let me know 6 months from now and tell racer he was wrong

 

[Ericehess]

let me know 6 months from now and tell racer he was wrong

Haha..sorry to cause controversy. I'm gonna just be more careful and try to keep the batteries close to storage voltage..between me and my son we use atleast one battery each a day..2 on weekends..3 if we use boat too..gotta have a system in place..should buy another good charger with storage setting. Thanks guys..really appreciate it.

 

[olds97_lss]

Save money now and get a charger that works better for what you do.

Store at 3.8V for the best life.

The issue with storing below that for any duration is the batteries lose charge over time and if they drop too low, they may not recover and even if they did, your charger may not allow you to charge them because it will assume the cells are bad/faulty. When storing them at full charge, it affects them differently. It builds up the internal resistance (IR). IR is effectively "wear". As batteries age, their IR goes up. This limits the capacity, run time, and current flow. So they store less and feel weak and run hot.

None of my trucks are set to stop at 3.8V. Thats 1/3 of the run time. I suppose I could buy more packs and get less wheel time, but I don't, They all run down to 3.4V which is still safe, but too low to not charge them back up to storage. After every run, I either discharge down to storage, or charge back up to storage. I never let them sit for more than a few hours charged or discharged. It's just a habit now.

 

[Ericehess]

Save money now and get a charger that works better for what you do.

Store at 3.8V for the best life.

The issue with storing below that for any duration is the batteries lose charge over time and if they drop too low, they may not recover and even if they did, your charger may not allow you to charge them because it will assume the cells are bad/faulty. When storing them at full charge, it affects them differently. It builds up the internal resistance (IR). IR is effectively "wear". As batteries age, their IR goes up. This limits the capacity, run time, and current flow. So they store less and feel weak and run hot.

None of my trucks are set to stop at 3.8V. Thats 1/3 of the run time. I suppose I could buy more packs and get less wheel time, but I don't, They all run down to 3.4V which is still safe, but too low to not charge them back up to storage. After every run, I either discharge down to storage, or charge back up to storage. I never let them sit for more than a few hours charged or discharged. It's just a habit now.

Thanks for the reply! I've been bringing them up to storage voltage after running them lately. They charge pretty quick from there so it hasn't been too difficult..takes 30-45 mins or so to charge to full at 1C.

 

[Ericehess]

Thanks for the reply! I've been bringing them up to storage voltage after running them lately. They charge pretty quick from there so it hasn't been too difficult..takes 30-45 mins or so to charge to full at 1C.

I want to get a charger that can charge/discharge multiple batteries at once..any suggestions?

 

[olds97_lss]

Not many chargers can discharge at a very high rate.

My dynamite 4x100 will discharge 4 packs at 5A/50W and charge them at 10A/100W. Which is fine for 3S 5000mah lipo's, but a bit lacking on wattage for higher cell count packs.

I just got a couple revolectrix GT500's which can output 20A/500W with a 24V PSU driving them. I parallel charge a couple 3S packs on them both at a time at 15A. They can only discharge at 8A/50W as well internally.