Handwarmers for battery in cold weather

[damoncooper]

What do folks think of this idea for cold temp operation. These are 2.5" X 3" and work for up to 10 hours.

If we had a holder for the outside sides of the battery cage that accepted a handwarmer slid in and kept secure it would help keep things in battery land cozy, even among battery swaps.

Need to have a solid outside side wall and probably a mesh inner wall to let heat into the battery compartment but keep the cold out.

Especially in light of the 1.6FW update this might be a great way to make sure you aren't performance limited at a critical moment.

Thoughts?

 

[damoncooper]

Some data to accompany this thought...

 

[damoncooper]

Looking at the TB48 specs, the Operating Temperature Range is quoted as -10 to 40° C.

Which I presume means ambient air temp, as the battery internal temp itself can get quite a bit hotter than that.

So you'd just need to be careful not to enclose the battery so much that it would get into a dangerously high internal temperature.

 

[damoncooper]

View attachment 5367
The irony was too much for me not to post the photo of when I purchased them.

Nice! Right after upgrading to 1.6? .

 

[damoncooper]

Anyone know what internal batt temp would trigger a shutdown or dangerous situation?

 

[The Editor]

I don't think they share that information with those they seem to deem idiots as they withhold all pertinent technical data as if we aren't capable of understanding it. I didn't update to the latest batch of performance removal firmware improvements. Hearing of PRO owners having issues with windy but reasonable conditions told me all I need to know about the latest knee jerk firmware reaction. I made the decision to be hyper careful with what temperatures I utilize my batteries. The hand warmers were a solution as I do own DJI battery warmers but just cant wrap my head around using battery power to heat the battery for 15 minutes that only lasts in the aircraft for 14 minutes in the first place. They had their best guy on the design of that piece of equipment I'm sure.

The battery warmers are actually quite good IF you are already flying and place the next battery in the warmer to get ready for the next flight.
This way you actually only need to worry about the temperature of the first pack you fly with. All others after that are nice and toasty and ready to put straight in the aircraft pretty much irrespective of outside temp.

 

[The Editor]

Anyone know what internal batt temp would trigger a shutdown or dangerous situation?

I already have this question out on Driving Force and with R&D.

 

[The Editor]

I don't doubt their effectiveness but what everyone who has obviously imbibed in far too much DJI Koolaid seems to forget to share is how much flight time are you sacrificing operating an electrically powered heater for 15 minutes on a battery with limited mAh.

Around 4-5% or 45 seconds(ish)

 

[The Editor]

Ok so in the 5% neighborhood. Not as horrible as I would have expected but what is curious to me is why they wouldn't design a heater that maintained two at a time and operated off the same lipo utilized in the controllers. They could be charged from the same equipment and as we all know are extremely efficient. If you were a pro with 6 or 8 packs you would need 3 or 4 and that wouldn't present a large issue in preparation having them charged and ready to go for a shoot.

PAH....you're trying to apply logic where DJI is concerned - can you spot your mistake?

 

[damoncooper]

I was actually thinking the battery warmers might make decent discharge devices but if they draw that little current maybe not

 

[Luminoz]

What do folks think of this idea for cold temp operation. These are 2.5" X 3" and work for up to 10 hours.

If we had a holder for the outside sides of the battery cage that accepted a handwarmer slid in and kept secure it would help keep things in battery land cozy, even among battery swaps.

Need to have a solid outside side wall and probably a mesh inner wall to let heat into the battery compartment but keep the cold out.

Especially in light of the 1.6FW update this might be a great way to make sure you aren't performance limited at a critical moment.

Thoughts?

View attachment 5362

I use the crap out of chemical handwarmers to keep batteries warm before I use them. Buy them in bulk and keep a few packs in your flight Kit.

 

[SuperPete]

I actually I ran in to same problem doing project at the snow resort, after that I made a battery insulation shield, it wraps around battery compartment on outside of the drone and all it does is prevents heat from escaping, it's in the test mode now, Once it's tested and good, you should be able to buy it, ill be probably selling on eBay or something. Another week or two. Good thing about it you only need one shield vs stickers you buy from DJI that you need set for ea battery. Shield you can put on and remove fast anytime you want, on the fly when needed.
Anyway, something to look forward too in near future...

 

[Kris]

Hand warmers and or toasty toes and a neoprene can cooler for while she is in the air to hold out the cold? Any thoughts? Finally working outside most of my life has paid off.


Sent from where the wild things were using Tapatalk

 

[ovisopa]

I actually I ran in to same problem doing project at the snow resort, after that I made a battery insulation shield, it wraps around battery compartment on outside of the drone and all it does is prevents heat from escaping, it's in the test mode now, Once it's tested and good, you should be able to buy it, ill be probably selling on eBay or something. Another week or two. Good thing about it you only need one shield vs stickers you buy from DJI that you need set for ea battery. Shield you can put on and remove fast anytime you want, on the fly when needed.
Anyway, something to look forward too in near future...

Pete, I also made myself some shielding around battery compartment as this autumn I flown a lot in early mornings with temperatures around -2 degrees C and in the evening with +10 .. so after first test with the original neoprene stickers I understood they're no good to me as in the morning I had to put them on and in the evening get them off .. In the past few days I flown alot using Map Pilot, so far ~100km, all the flights ware at a temperature ranging -8 to -2 degrees C, and the thick balsa wood I used to cover the compartment it's been very effective, on landing the battery temperature ranged from 28 to 40 degrees C. Today I checked the temperature also before flight and it was ~17 degrees.

Now I made a temperature logger but so far is just on a breadboard with the wires hanging out, I really want to see the exact temperature inside the battery compartment and outside while flying, and to test different materials. Will let you guys know how it goes.

 

[damoncooper]

Hand warmers and or toasty toes and a neoprene can cooler for while she is in the air to hold out the cold? Any thoughts? Finally working outside most of my life has paid off.


Sent from where the wild things were using Tapatalk

Do you mean putting the warmers and battery in the can cooler prior to flight?

Interesting if we could figure out how to wrap the battery compartment with the stuff the can cooler is made of?

 

[damoncooper]

I actually I ran in to same problem doing project at the snow resort, after that I made a battery insulation shield, it wraps around battery compartment on outside of the drone and all it does is prevents heat from escaping, it's in the test mode now, Once it's tested and good, you should be able to buy it, ill be probably selling on eBay or something. Another week or two. Good thing about it you only need one shield vs stickers you buy from DJI that you need set for ea battery. Shield you can put on and remove fast anytime you want, on the fly when needed.
Anyway, something to look forward too in near future...

Got a picture of that? Sounds great.

 

[SuperPete]

Here is quick sneak peak.

 

[Kris]

Found this concerning sheets of neoprene. Will try to make a mold of battery compartment and see what I come up with. Limited to an analog instant read and point and shoot thermometer but might be enough to show whether it's going to help or not.
Link to neoprene Neoprene Rubber Sheet | Sheet Rubber & Rolls


Sent from where the wild things were using Tapatalk

 

[xahhax]

I keep the batteries in my pockets close to my body and temp at take off is above 15C, then i have no issue as it starts to warm up with current draw.
Flew at 9000ft in the Alps in winter using this technique and never went below 15C.

 

[gregdd]

Yes if batteries are warm to start it has to be pretty **** cold to need hand warmers attached to craft. Just some kind of insulation on outside of craft.

I made insulation with coroplast and used thick elastics to secure it. Todays test results with my insulators:
Outside temp: 0c
Starting battery temp: 10c
After 10 mins of flight: 40c

My thinking is that without the insulation today the battery still would have warmed up in flight.

I just keep a cooler with batteries and handwarmers in it before flight.