LiPo batteries storage

[old man mavic]

@Oman ,good points from the post above #20
its very easy to become over cautious about batteries in any sort of devices we have in our homes ,and i am not saying for one minute, that they don't have the potential to cause a serious issue if they do ignite ,but the moments when that is most likely to happen ,are if they are miss handled
or allowed to become excessively hot ,or punctured in some way
DJI have built in many safeguards to mitigate the chances of ignition taking place ,and also its one of the reasons ,why with proper care and and storage ,the chances of such an event taking place are very unlikely

 

[maelstrom]

As previous posts have already mentioned, it's HIGHLY unlikely (but not absolutely impossible, of course) that genuine, undamaged Mavic batteries, charged in the original charger with the original power adapter will pose a serious danger when charging.

However, what is worth mentioning (as I did in another post) is that LiPo bags give you a false sense of security. They provide very little real protection in the event of a thermal runaway:

To view this content we will need your consent to set third party cookies.
For more detailed information, see our cookies page.

Accept third party cookies

 

[Kuiper Denizen]

If there’s someone who has had a fire, explosion, battery separation, or any accident that can be traced to the battery, would you please share what signs you noticed that you later felt could have warned you?

I’m aware of battery swelling, excessive temperature (during flight or charging), and obvious physical damage, but how much of any of these should be taken as a definite warning that disaster is impending?

I’ve read that charging cycles on lithium batteries, in general, are counted when from depletion to fully charged, but aren’t DJI batteries counting any recharging, regardless of its per cent charge at start?

And is there any recharging amount that should signal retirement regardless of a battery’s observable condition?

 

[Droning on and on...]

One thing to consider is getting a Lipo Bag. I store my extra batteries in these and they don't cost that much. The remainder of my batteries I keep in my cases.

Is that where you put your cell phone at night, or is it plugged in, sitting on your nightstand, a few feet from your head?

Just saying

 

[BobaFut]

If there’s someone who has had a fire, explosion, battery separation, or any accident that can be traced to the battery, would you please share what signs you noticed that you later felt could have warned you?

I’m aware of battery swelling, excessive temperature (during flight or charging), and obvious physical damage, but how much of any of these should be taken as a definite warning that disaster is impending?

I’ve read that charging cycles on lithium batteries, in general, are counted when from depletion to fully charged, but aren’t DJI batteries counting any recharging, regardless of its per cent charge at start?

And is there any recharging amount that should signal retirement regardless of a battery’s observable condition?

I could be wrong on this, but my understanding is that a lot of battery fires are actually the result of bad *chargers* and not necessarily bad batteries, just to give you one more hard-to-observe variable to worry about.

 

[Droning on and on...]

I could be wrong on this, but my understanding is that a lot of battery fires are actually the result of bad *chargers* and not necessarily bad batteries, just to give you one more hard-to-observe variable to worry about.

Pretty much.

DJI batteries are immune to this problem. The integrated BMS makes it impossible for a power supply to overvoltage the cells.

 

[Kuiper Denizen]

So, I guess the only sign that it’s time to retire a battery is when it becomes bloated enough that it takes an extra push to get it into the drone. If not that, then when it becomes so easy to remove removal can be with just a tug, meaning it could pop loose in flight.

Is that really better than its maximum temperature in flight or at landing?

 

[Droning on and on...]

So, I guess the only sign that it’s time to retire a battery is when it becomes bloated enough that it takes an extra push to get it into the drone. If not that, then when it becomes so easy to remove removal can be with just a tug, meaning it could pop loose in flight.

Is that really better than its maximum temperature in flight or at landing?

Actually, swelling is a sign of a problem. The battery should be carefully disposed of.

The best indicator that it's time to retire a LiIon chemistry battery is reduced capacity. It's at end of life when you get unacceptably short flight times from it.

"Unacceptable" is subjective and up to you.

 

[MAvic_South_Oz]

Is that really better than its maximum temperature in flight or at landing?

Swelling on the battery is definitely a sign of problems with the chemistry.

Temperature, yes, much hotter to touch at landing and when charging is a good thing to get used to feeling during those times, compare to normal feel at these times, and excessive temps is also a sign of a battery reaching end of life stage.

Keep in mind a battery will be hotter to the touch after some sports mode flight, or battling a head wind just before landing, so know what the normal feel is like in those situations too.

Cell balances will also show greater differences to normal when a battery is getting near its end.

 

[Kuiper Denizen]

Swelling on the battery is definitely a sign of problems with the chemistry.

Temperature, yes, much hotter to touch at landing and when charging is a good thing to get used to feeling during those times, compare to normal feel at these times, and excessive temps is also a sign of a battery reaching end of life stage.

Keep in mind a battery will be hotter to the touch after some sports mode flight, or battling a head wind just before landing, so know what the normal feel is like in those situations too.

Cell balances will also show greater differences to normal when a battery is getting near its end.

Keeping an eye on cell balance is the objective type of suggestions I was looking for. Thank you.

 

[Felix le Chat]

Another ɓattery question, I would like to hear some responses on how and where to store LiPo batteries when not used for a while. I have been flying for a while, so far so good. Just wondering if there is any updates on Safe storage. I have seen some reports on battery . Right now I store in the house , because its either too cold or too hot in the garage. I welcome any new suggestions.
Thanks oman

Having read about li-ion and lipo battery fires over the last four years, they mainly seem to be caused by either uncontrolled overcharging, low-rent construction and cheap components, or mishandling. I keep a careful eye on all my DJI batteries and the 'intelligent' board in them seems to do an exceptionally good job. It might drive me nuts, but the auto-discharge feature triggered by idleness is a stroke of genius. All my IFB's are charged on the kitchen worktop and as soon as the cells in each have finished the final balancing cycle: they cease to draw current and switch themselves off. So far: 5 years and not a single problem.

 

[Melvoid]

The batterys in the controller don't get banged around like the ones on the model planes or FPV drones so they get to stay inside the house, but I still charge them in the workshop as opposed to the house. just for safety sake.

I'm charging mine on the kitchen counter as we speak.... Now I'm scared.

 

[Melvoid]

I store my dji batteries in a metal cabinet in the house (cool and dry) When not in use I keep them at 60% Even though the chance of fire is pretty slim with the intelligent batteries I still like the metal idea. I store my RC LIPOs OUTSIDE in my workshop they are in concrete blocks I place them in the little space. The R. C. Batteries are much more Risky than the DJIs so they stay outside. Many I know use ammo cans from the surplus store.

So, I've heard a few people saying to store them at 60%. I know that the charge decreases if they're unused for awhile, Does it stop when it reaches 60% (assuming you haven't changed the settings)?

 

[Cafguy]

No the decrease will not stop BUT by keeping your batteries at the storage charge {60%} you will get more cycles from your drones battery I recommend a charger that has a switch or an option for a storage charge.

 

[old man mavic]

@Melvoid the 60% is just a number that equates to around 3.7v per cell ,which is the recomended storage voltage ,but even then over a period of many months that voltage will gradually drop till it, can cause the cell to no longer take on a charge ,to try to overcome this ,
the BMS built into the battery case,is supposed to react to the overal combined cell voltage drop and put the battery into sleep mode ,before this point is reached, but despite the BMS doing its best to try and prevent idividual cell damage taking place ,it still requires the pilot, to fly , and store the batteries, in a manner that is not detrimental to the charge cycle life of the battery ,

 

[Melvoid]

No the decrease will not stop BUT by keeping your batteries at the storage charge {60%} you will get more cycles from your drones battery I recommend a charger that has a switch or an option for a storage charge.

So if I found such a charger, would I just keep the batteries on it all winter?

 

[Cafguy]

So if I found such a charger, would I just keep the batteries on it all winter?

NO lol you need to check your batteries every few weeks and keep them at a certain level.
Bet you didn't realize that when you got your Drone it came with those little guys that NEED care. Your battery will last Much longer by Taking care of it in this manner it has been proven. NEVER just throw them in a drawer and forget about them unless you want them to DIE.

 

[Melvoid]

NO lol you need to check your batteries every few weeks and keep them at a certain level.
Bet you didn't realize that when you got your Drone it came with those little guys that NEED care. Your battery will last Much longer by Taking care of it in this manner it has been proven. NEVER just throw them in a drawer and forget about them unless you want them to DIE.

They're too @#$%^ expensive to allow them to die.