Smart Battery Charging at High Temperature

[Eyeup Aerial Solutions]

Hi all,

I'm sure this is correct but would love confirmation from somebody in the know. Inspire 1 batteries will not charge if too hot (above around 35degrees?) Is it safe to attach them to a charger (or 4-way hub) while hot and will they start to automatically charge once they get down to a safe temperature?

I only ask as I have a gig coming up that will require lots of battery changes and charges to keep going all day and I'd rather not have the hassle of trying to keep tabs on whether an individual battery is "ready" to go into the charger.

Apologies if this has already been covered elsewhere Mr Editor.

 

[Phatzo]

Hi
i think if i recall correctly that it is not recomended to charge when still "hot" and chaging should be done when battery is at ambient temp i.e. around 25C or room temp... i used to put them infront of the A/C vent in summer so i can put them up asap...
you should not put them up when still hot.

 

[Eyeup Aerial Solutions]

Hi
i think if i recall correctly that it is not recomended to charge when still "hot" and chaging should be done when battery is at ambient temp i.e. around 25C or room temp... i used to put them infront of the A/C vent in summer so i can put them up asap...
you should not put them up when still hot.

But doesn't the battery recognise that it is hot and just refuse to charge until its core temperature has dropped sufficiently?

 

[Phatzo]

But doesn't the battery recognise that it is hot and just refuse to charge until its core temperature has dropped sufficiently?

i would not trust the "smart" pcb... i posted some video microscope pics in the battery mod thread and the comments speak for themselfs... in short: my 6year old son could do better in soldering. lol
so, keeping that in mind and the original fuction, yes it should not let you charge when "hot" but i never checked as one does not put warm or just after landing hot batteries on the charger. it is what i learned from before DJI stuff flying...

i will check for you and try to put one on when still hot (45C degrees) and let you inow if i put a chicken on top because i had a little fire or if the charging started when the batt was cold enough. LOL

cheers
Martin

 

[ianwood]

Batteries come off hot and you should cool them down for a period before charging them back up.

 

[elguapo]

Also, if you attempt to charge them while they're hot you are running the risk of ending with a swollen battery. This happened to me with the battery of a Phantom 3 Pro.

 

[Eyeup Aerial Solutions]

Ok, I think I'll run my own test when the wind and rain dies down here.

I'm aware of the need for cooling, I just need to understand how "smart" the batteries are, given that we know they have a thermal sensor built in. The job I have is really tight on batteries even with a P4P to fly for a couple of sessions every 3 batteries. It'll be non-stop flying for the first 4 hours+ so I'll have a trusted buddy on to check battery temps using my spare aircraft before sticking on charge if necessary.

 

[SanCap]

When I had my I1 I would put some freezer packs in a cooler with a towel over them and set the warm/hot batteries on them to help cool them down. I also left the charged batteries in there also when we had outside air temps higher than 90° here in SW Florida so they started off cooler. That is a nice thing about the Inspire 2, the batteries do not get nearly as hot as the Inspire 1 batteries did.

 

[The Editor]

Ok, I think I'll run my own test when the wind and rain dies down here.

I'm aware of the need for cooling, I just need to understand how "smart" the batteries are, given that we know they have a thermal sensor built in. The job I have is really tight on batteries even with a P4P to fly for a couple of sessions every 3 batteries. It'll be non-stop flying for the first 4 hours+ so I'll have a trusted buddy on to check battery temps using my spare aircraft before sticking on charge if necessary.

The temp sensing thermister can only monitor one area of the pack being where it is located. This means at best it is monitoring the two cells it is sandwiched between. The other cells in the pack can be hotter or colder than this particular sample point.
I would not and do not trust a cheap probe to tell me when it's safe to recharge my packs.
Ideally you should allow them to cool to ambient (a good 20-30 minutes) after a flight before putting them on charge.
If that is not possible, I would invest in more batteries and build the cost into what you charge the client.

 

[Donnie Frank]

Hi all,

I'm sure this is correct but would love confirmation from somebody in the know. Inspire 1 batteries will not charge if too hot (above around 35degrees?) Is it safe to attach them to a charger (or 4-way hub) while hot and will they start to automatically charge once they get down to a safe temperature?

I only ask as I have a gig coming up that will require lots of battery changes and charges to keep going all day and I'd rather not have the hassle of trying to keep tabs on whether an individual battery is "ready" to go into the charger.

Apologies if this has already been covered elsewhere Mr Editor.

That's the kewl thing about smart batteries and why we pay $200 a pop. Yes, put them on the charger hot. Your battery will tell the charger when it's ready. That said, if given a choice, charging completely cooled batteries is probably better than charging warm batteries. But when in the field, under the gun, like I was 2 days ago, we stick them on the charger immediately, because we know the battery will tell the charger when its ready. I have 4 batteries with roughly 50 charges each, all running strong. I think my secret is that I meticulously run them down to 0% every 10 charges, just as the instructions say to do. Note: 0% in the Go App = roughly 3.3v/cell.

Good luck!

 

[Eyeup Aerial Solutions]

That's the kewl thing about smart batteries and why we pay $200 a pop. Yes, put them on the charger hot. Your battery will tell the charger when it's ready. That said, if given a choice, charging completely cooled batteries is probably better than charging warm batteries. But when in the field, under the gun, like I was 2 days ago, we stick them on the charger immediately, because we know the battery will tell the charger when its ready. I have 4 batteries with roughly 50 charges each, all running strong. I think my secret is that I meticulously run them down to 0% every 10 charges, just as the instructions say to do. Note: 0% in the Go App = roughly 3.3v/cell.

Good luck!

Cheers Donnie,

I think only the first 3 charges will be "at risk". After that, the length of the charging cycles with the chargers I've got will ensure the batteries have at least 45 mins to cool down. I'll makes sure they're placed somewhere nice and cool after use. Probably under the marshals tower I'll be operating from.

 

[Donnie Frank]

Cheers Donnie,

I think only the first 3 charges will be "at risk". After that, the length of the charging cycles with the chargers I've got will ensure the batteries have at least 45 mins to cool down. I'll makes sure they're placed somewhere nice and cool after use. Probably under the marshals tower I'll be operating from.

If I recall, there IS a "break in" period. I've been known to stick batteries in the fridge and even the freezer. I use a timer, because ultimately, I forget they're in there....<:^0

I was recently on set shooting for 10 hours. We had 13 batteries with us and brought along a third person (an Electrical Engineer) who did nothing but tend batteries all day. We paid him $500. That is how important good battery management is on set. When the batteries were spent, he would put them in the shade in an upright position so the wind would cool them off ASAP. We managed to go the entire day without running out of batteries. $500 well spent.

We had 2 chargers: 180 watt, and a 100 watt, and a hub. I think the hub was on the 180 watt charger. I don't know, as I was too busy operating camera to be concerned with batteries.

According to the battery manual:

"DO NOT charge battery immediately after flight, because the battery temperature may be too high.
DO NOT charge the battery until it cools down to near room temperature. Charging the battery
outside of the temperature range of 32°-104° F (0°-40° C) may lead to leakage, overheating, or
battery damage."

According to the Inspire 1 manual:

"Temperature Detection: The battery will only charge when the temperature is between 0 °C(32°F) and
40°C (104°F).

I do the latter, and have for quite a while. The built-in "Temperature Detection" seems to work well.

Regards,

Donnie