How do YOU physically store your drone batteries for long periods?

[Slade]

OKay, I KNOW I won't get too much, if any chance to fly this winter, so that means my mavic and spark batteries will need to be "stored." I am now wondering what kind of containers, etc. you all put your batteries in for protection-- just in case, they would--God forbid--catch fire--especially when we aren't home--certainly don't want them to start burning, start a fire, or even spread toxic fumes for my dog and cat if we aren't home. I don't have a basement, so they cant be kept there, and my garage is not heated--gets below -40 and below with the windchill sometimes, so can't keep them outside, so..it's in the house....what do you all do?????THANKS!

ALL my drone batteries are stored in Fireproof battery bags. I recently saw a video on You Tube where an experienced drone pilot burned his house up and lost thousands of dollars in drones and batteries. For a few dollars on Amazon you can add a layer of protection.

 

[GGehret]

Weird. Autodischarge is not even started yet (it starts at 10 days) and every time you check the whole process starts over... ie 10 more days until auto discharge restarts.

I know, that's exactly what I thought when he told me that on "chat." I didn't put too much stock in that advice. Does not line up with everything else we know about these batteries.

 

[GGehret]

ALL my drone batteries are stored in Fireproof battery bags. I recently saw a video on You Tube where an experienced drone pilot burned his house up and lost thousands of dollars in drones and batteries. For a few dollars on Amazon you can add a layer of protection.

I bought a few last night, and I'll probably overkill and put them on or in a cinderblock too.

 

[GGehret]

I bought a few last night, and I'll probably overkill and put them on or in a cinderblock too.

Let’s get back to this vague assertion. Will you be otherwise busy this winter, whereby you will be unable to fly, or are you worried about the winter temps? Winter flying is awesome, but there are a few requirements to make it problem free..

Well, for me it's a combo--my time is limited with winter. I am a teacher and usually don't get home until after dark--you know how short the winter days are, and I live in the "boonies" so there's NOTHING to see if I fly at night. Also, it gets VERY cold--below the recommended 14F degrees--here in the winters. So, I just know my times and opportunities to fly thru prob. sometime in December thru February to early March are going to be very limited.

 

[Deleted member 93449]

My understanding is most battery fires occur when charging the batteries rather then during storage. Storage conditions (temperature and voltage) have more to do with prolonging the life of the batteries versus a fire hazard. I've read recommendations from 40% to 80% as the "ideal" storage voltage at room temperature (~25°C). If someone has actual test data to show which is the optimal voltage I'd be interested in reading it.

 

[theDRONEranger]

For Long-term storage we have options not available to you but I'll let you know how we've done it for years and maybe you can come up with your own processes.

All my LiPo (smart or not) that are being stored long-term are in my basement and at Storage Level (40%-60%) charge. We take them and give the charge a smal "boost" 1x every 2 months.

I have a small "bank" of CMU (cinder blocks) sitting on my basement (concrete) floor and each battery goes down into a "Cell" in a block. This way if one ignites it can't ignite anything else or any other batteries. Also for nonSmart batteries (we just haven't done this with the SMART ones yet and may not do it) each cell has a large zip lock plastic bag filled with common swimming pool sand laid over it. The THEORY (never tried to prove or disprove it) is it it gets hot enough to melt the bag the sand will fall and hopefully help to contain the situation to some degree. I admit our methods are Old School, Over Kill, and maybe even a waste of time in some instances but it gives us peace of mind and that means a lot to us.

I don't have an air evacuation/venting system in the event of a gas release during a fire but I did install a smoke detector (wirelessly connected to the rest of the ones in the house) directly over this work area. This work area is only a few feet away from a Double Door so if I were home during this event (or shortly there after) I could easily open the doors and turn on a floor fan to ventilate the fumes to the outdoors.

Unfortunately none of these techniques are available to you because you don't have a masonry area that is somewhat conditioned to store yours in. Hopefully this gives you some ideas and I'm sure others will chime in with some additional and possibly even better suggestions.

I really like your concept of storage, but let me ask . . . “What is wrong with letting the LiPo’s simply fully discharge and go into hibernation mode, same as when they are shipped?” After all, isn’t that how DJI does it?

 

[GIZMO+]

OKay, I KNOW I won't get too much, if any chance to fly this winter, so that means my mavic and spark batteries will need to be "stored." I am now wondering what kind of containers, etc. you all put your batteries in for protection-- just in case, they would--God forbid--catch fire--especially when we aren't home--certainly don't want them to start burning, start a fire, or even spread toxic fumes for my dog and cat if we aren't home. I don't have a basement, so they cant be kept there, and my garage is not heated--gets below -40 and below with the windchill sometimes, so can't keep them outside, so..it's in the house....what do you all do?????THANKS!

I recently bought an ammo box to put my batteries in. We lost our whole house to a fire back in 2014. So now I'm a little hypersensitive to the possibilities. You can never be too careful!!!

 

[BigAl07]

I really like your concept of storage, but let me ask . . . “What is wrong with letting the LiPo’s simply fully discharge and go into hibernation mode, same as when they are shipped?” After all, isn’t that how DJI does it?

I don't have a link handy (it's been a day or two) but at some point DJI said to give them a boost/charge every few weeks or something like that. That's when we wrote that into our SOP for battery storage.

All this talk about battery storage makes me realize I could (should) simplify my life and sell some of my non-active aircraft and peripherals.

 

[kingsnake11]

You just have to respect that fact that LiPo batteries can be problematic and need to be cared for properly. I still fly a lot of RC fixed winged aircraft and so I follow the safety protocols learned over the years. I use an intelligent parallel charger and never charge at more than 2C...that prolongs battery life...and if you charge to 4.18 V per cell, your battery lasts longer too. Unfortunately, I don't see those as options when charging the Mavic batteries...unless they're available in some third party charger that I don't know about. I charge over a marble slab, surrounded by bricks, and never leave them unattended at charging. Class C-D fire extinguisher is always within reach.

When it comes to storage, I keep my discharged batteries in Metal ammo cans. I use the intelligent charger to discharge to storage voltage, 3.80 to 3.85 per cell, and I also have a specific discharger for that task to select discharge rates and can set the final storage voltage. While drawing down the telemetered storage percentage is a good idea, and I agree that 40 to 60% range is a good rule of thumb, it's more important to know the voltage per cell for storage. Like just about everything in RC, there is a debate and differing opinions but generally, the voltage per cell range I stated has broad agreement.

Given how **** expensive the batteries are, you owe it to yourself to take care of them....and for safety reasons too. You also have to make sure the battery is in good physical shape. Swollen batteries from overcharging...or over discharging can pose a higher risk, as does any battery that was in a crash and shows crash damage.

 

[FASTFJR]

I keep Each One (4) in a fireproof battery bag

 

[johnmeyer]

LiON batteries have the potential to explode or catch fire. But how often does this happen, and is it really a problem we need to worry about?

Short answer: no.

I have two justifications for this answer. First is the "do you know anyone?" test. We all have many LiON batteries in our phones, laptops, high-powered flashlights, vaping pens (some people) and, of course, electric cars. With all that equipment and with hundreds of friends and acquaintances, I do not know one single person who has ever had a battery catch fire or blow up.

My second justification for my statement is from basic research. I was easily able to find sensational news stories about "spontaneous" LiON fires or explosions, but a little reading showed almost all of those to not be spontaneous at all, but instead were caused by some sort of accident (dropping, crushing, shorting, etc.). This includes the Consumer Reports article which quoted the FAA study about multiple LiON fires aboard aircraft. Most (not all) of those, when you read the report, involved dropping boxes or having the batteries in a box where the battery terminals were allowed to touch a metal object packed in the same box.

So, compared to gasoline, which most of us store in the garage in cans and in our cars, I think these batteries are pretty darned safe, and I think are extremely unlikely to cause a problem.

As for long-term storage, DJI includes circuitry that will discharge the battery to under 60% if you let it stand for about ten days. This is more for extending the life of the battery than for safety, but it obviously reduces the impact of any overheating, no matter how remote that possibility. Since the DJI circuits take care of the discharge, you don't need to do it.

To avoid anything touching the battery terminals, I created some terminal covers. However, if you have a fireproof bag (which I do), that will suffice.

So, get the bags, let the DJI circuits manage the discharge, don't store the batteries next to oily rags or old newspapers, and then go and find something else to worry about.

 

[msinger]

DJI support told me to check them every 5 days...that's REALLY inconvenient, I think

For sure! Your batteries will be fine if you follow these tips while storing them:

HOW TO: Maintain and store your DJI Mavic batteries | Mavic Help

Mavic Help is a site for help with DJI Mavic drones. Find the latest fixes, how-tos, guides, accessories, modifications, and more.

www.mavichelp.com

 

[DanMan32]

MA and M2 batteries no longer reset the day to discharge counter if you just press once to view the SoC.

As for accidental terminal short, that won't do anything with the battery off, and accidental turn on is unlikely. You have to press, then press and hold for two seconds.

 

[GGehret]

For sure! Your batteries will be fine if you follow these tips while storing them:

HOW TO: Maintain and store your DJI Mavic batteries | Mavic Help

Mavic Help is a site for help with DJI Mavic drones. Find the latest fixes, how-tos, guides, accessories, modifications, and more.

www.mavichelp.com

Thanks. I read this page a few weeks ago. Still good to review again.

 

[GGehret]

LiON batteries have the potential to explode or catch fire. But how often does this happen, and is it really a problem we need to worry about?

Short answer: no.

I have two justifications for this answer. First is the "do you know anyone?" test. We all have many LiON batteries in our phones, laptops, high-powered flashlights, vaping pens (some people) and, of course, electric cars. With all that equipment and with hundreds of friends and acquaintances, I do not know one single person who has ever had a battery catch fire or blow up.

My second justification for my statement is from basic research. I was easily able to find sensational news stories about "spontaneous" LiON fires or explosions, but a little reading showed almost all of those to not be spontaneous at all, but instead were caused by some sort of accident (dropping, crushing, shorting, etc.). This includes the Consumer Reports article which quoted the FAA study about multiple LiON fires aboard aircraft. Most (not all) of those, when you read the report, involved dropping boxes or having the batteries in a box where the battery terminals were allowed to touch a metal object packed in the same box.

So, compared to gasoline, which most of us store in the garage in cans and in our cars, I think these batteries are pretty darned safe, and I think are extremely unlikely to cause a problem.

As for long-term storage, DJI includes circuitry that will discharge the battery to under 60% if you let it stand for about ten days. This is more for extending the life of the battery than for safety, but it obviously reduces the impact of any overheating, no matter how remote that possibility. Since the DJI circuits take care of the discharge, you don't need to do it.

To avoid anything touching the battery terminals, I created some terminal covers. However, if you have a fireproof bag (which I do), that will suffice.

So, get the bags, let the DJI circuits manage the discharge, don't store the batteries next to oily rags or old newspapers, and then go and find something else to worry about.

THANKS for the info. SAfety bags have been ordered and are on their way--one for my smart controller too.

 

[GGehret]

I recently bought an ammo box to put my batteries in. We lost our whole house to a fire back in 2014. So now I'm a little hypersensitive to the possibilities. You can never be too careful!!!

DO you close the ammo box tightly as constructed. I read somewhere???? that person said don't close it tightly--could build up pressure and explode if fire does start inside. Just wondering how you use your ammo box. Thks

 

[DerekJG]

HI, this thread is a bit scary as I have happily been recharging batteries at home often when absent with no problems. I am now inclined only to charge while I am present. This poses the question - is it safe/ok to stop and start charging the same battery until fully charged?

 

[msinger]

is it safe/ok to stop and start charging the same battery until fully charged?

Yes.

 

[WithTheBirds]

I really like your concept of storage, but let me ask . . . “What is wrong with letting the LiPo’s simply fully discharge and go into hibernation mode, same as when they are shipped?” After all, isn’t that how DJI does it?

Why would you suspect the battery might be in hibernation mode when purchased? There is a shipping mode state that can be set in manufacture that completely turns off the monitoring modes in the SOC. There is no question that this state would have some impact (minor) in reducing discharge while stored. It might also reduce the accuracy if the fuel gauging algorithm, if only temporarily. Hibernation state still provides for routine cell measurements by the SOC however they are less frequent.

 

[DerekJG]

Yes.

Thanks for the reassurance