Battery Observations

[Deleted member 94047]

[Edit #2]: From what has been pointed out by several posters regarding the effects of cold storage on battery health, I think there is a strong chance that my "insights" below about the effects on battery health of exposure to cold (at time of delivery) are wrong. At best, they are mere speculation.

I wanted to share a few an observations about batteries. I have a Mavic Air but I guess this will apply to all Mavics; their batteries at least. I have three batteries; one came with the drone from DJI, the second was purchased from a physical store, and the third from Amazon. All three were bought with in two weeks of each other and have roughly the same amount of cycles on them (two have 35 cycles, one has 33). I have flown all of them in pretty much the same conditions and have treated them with the same level of care (I fly with them with in 12hrs of charging or less, never fly them below 20%, and charge them to 60% afterwards; I store them in a dry, cool place at room temperature, etc).

Battery #1 Manufactured 28-Apr-2018 [Came with drone]
Battery #2 Manufactured 15-Aug-2018 [Purchased from physical store]
Battery #3 Manufactured 09-Jun-2018 [Purchased from Amazon]

Of the three, Battery #2 is in top shape. It shows the least amount of deviations between cells, and gives me the most air time of the three. The other two batteries are not so great. They are still fine to fly with but show more pronounced cell deviations, and give me roughly 2 minutes less air time as compared to battery #2. What could possibly explain this difference? Production date? May be. But I think there is another factor at play here. I bought the MA in late February of this year; I was in Germany and it was pretty cold. Both Battery #1 and #3 came in late in the evening and possibly spent the day in the back of a delivery truck in near freezing temperature. When I received them, they were cold, very cold. And that is the final leg of the delivery, who knows how they were stored before that? Battery #2 was in a display shelf in an air conditioned store. And I think this is why it is still in tip top shape.

My advice to you is, don't buy batteries during winter. And if you must buy them, you are better off purchasing them from a physical store than ordering them online.

Just sharing my experience is all. May your batteries last forever!

Edit: By the way, battery #1 is the one with the least amount of cycles and the one with the most issues.

 

[old man mavic]

it is a problem, we dont know how the batteries have been treated when we buy them ,and as you say storage is probably the biggest issue ,i think it is a bit of a lottery, apart from the 3 that came with my MPP flymore package, which i purchased from a reputable DJI outlet ,my other 2 came from the same place based in the uk.and so far with well over 40 odd charges on 4 and some 20 on my most recent purchase they all perform well( touch wood )

 

[MAVIC_2_YTS]

(I fly with them with in 12hrs of charging or less, never fly them below 20%, and charge them to 60% afterwards; I store them in a dry, cool place at room temperature, etc).

As I a new, and have seen allot of posts about this (only charging to 60% and then topping off before flights), is there a way to set the system to only charge to 60% or do you have to manually watch for it?

Thanks.

 

[Deleted member 94047]

As I a new, and have seen allot of posts about this (only charging to 60% and then topping off before flights), is there a way to set the system to only charge to 60% or do you have to manually watch for it?

Thanks.

Charging to only 60% is a good practice if you are not going to use the batteries with in the next day or two. If you are flying with them again within the next 24 - 48hrs, you might as well charge them to full capacity. But seeing that I tend to fly once every 5 - 7 days, I charge mine to about 60%. And yes, I have to watch them while charging - I take them off the charger as soon as the third led on the battery starts blinking which is roughly about 58 - 62% charge from my experience. I remember other here in this forum mentioning third party chargers that can be set to charge to a desired level but the stock DJI charger (including the charging hub) does not have this option.

 

[Deleted member 94047]

i think it is a bit of a lottery...

I hear you there, that may just be it. I just thought that in this case, the time spent in the delivery truck in near/below freezing temperatures might be what is in play.

 

[MAVIC_2_YTS]

Charging to only 60% is a good practice if you are not going to use the batteries with in the next day or two. If you are flying with them again within the next 24 - 48hrs, you might as well charge them to full capacity. But seeing that I tend to fly once every 5 - 7 days, I charge mine to about 60%. And yes, I have to watch them while charging - I take them off the charger as soon as the third led on the battery starts blinking which is roughly about 58 - 62% charge from my experience. I remember other here in this forum mentioning third party chargers that can be set to charge to a desired level but the stock DJI charger (including the charging hub) does not have this option.

Thanks for the informative reply! I still haven't taken my M2P out of the box yet so haven't actually seen the charging process (of course I've seen videos) but does the LED actually blink with each stage? meaning, once it's 2/4 charge the second LED will blind, and then so on?

Or, are you manually pressing the button and checking?

Thanks again!

 

[Deleted member 94047]

but does the LED actually blink with each stage? meaning, once it's 2/4 charge the second LED will blind, and then so on?

Yes, the led lights show the level of charge while the battery is being charged. You don't have to manually press the button at all. It works like this

 

[MAVIC_2_YTS]

Yes, the led lights show the level of charge while the battery is being charged. You don't have to manually press the button at all. It works View attachment 80309like this

That's handy! thanks again! The only other question I have is, I understand that after 10 days without use (including pressing the button on the battery) the battery will start an auto discharge process to bring it down to 60% and hibernate. Are we able to change this to another value? say 2 days?

Thanks again!

 

[THE CYBORG]

I hear you there, that may just be it. I just thought that in this case, the time spent in the delivery truck in near/below freezing temperatures might be what is in play.

Don’t think it was the cold you can store battery's long term in a freezer

 

[Deleted member 94047]

Are we able to change this to another value? say 2 days?

Depends on what model you have. On the MAVIC AIR and MAVIC TWOs, it is fixed at 10 days. You mentioned you have, or will soon have, a M2P; so you are out of luck in that regard.

 

[Deleted member 94047]

Don’t think it was the cold you can store battery's long term in a freezer

This is news to me. All my reading says LiPOs don't like to sit or work in extreme temps.

 

[MAVIC_2_YTS]

Depends on what model you have. On the MAVIC AIR and MAVIC TWOs, it is fixed at 10 days. You mentioned you have, or will soon have, a M2P; so you are out of luck in that regard.

Thanks! Yes, have the M2P so guess I will need to manually discharge.

Thanks again!

 

[old man mavic]

please do not put your batteries in your freezer

 

[charliesRig]

Great p

I wanted to share a few an observations about batteries. I have a Mavic Air but I guess this will apply to all Mavics; their batteries at least. I have three batteries; one came with the drone from DJI, the second was purchased from a physical store, and the third from Amazon. All three were bought with in two weeks of each other and have roughly the same amount of cycles on them (two have 35 cycles, one has 33). I have flown all of them in pretty much the same conditions and have treated them with the same level of care (I fly with them with in 12hrs of charging or less, never fly them below 20%, and charge them to 60% afterwards; I store them in a dry, cool place at room temperature, etc).

Battery #1 Manufactured 28-Apr-2018 [Came with drone]
Battery #2 Manufactured 15-Aug-2018 [Purchased from physical store]
Battery #3 Manufactured 09-Jun-2018 [Purchased from Amazon]

Of the three, Battery #2 is in top shape. It shows the least amount of deviations between cells, and gives me the most air time of the three. The other two batteries are not so great. They are still fine to fly with but show more pronounced cell deviations, and give me roughly 2 minutes less air time as compared to battery #2. What could possibly explain this difference? Production date? May be. But I think there is another factor at play here. I bought the MA in late February of this year; I was in Germany and it was pretty cold. Both Battery #1 and #3 came in late in the evening and possibly spent the day in the back of a delivery truck in near freezing temperature. When I received them, they were cold, very cold. And that is the final leg of the delivery, who knows how they were stored before that? Battery #2 was in a display shelf in an air conditioned store. And I think this is why it is still in tip top shape.

My advice to you is, don't buy batteries during winter. And if you must buy them, you are better off purchasing them from a physical store than ordering them online.

Just sharing my experience is all. May your batteries last forever!

Edit: By the way, battery #1 is the one with the least amount of cycles and the one with the most issues.

Great post I also have the similar experience with my MP1 3 battery the only one left was bought in a two pack 07-17
And still flying

And I quote from a wise soul
Olmanmavic
“ touching wood”

....... bah,bah,bah
Yada,yada,ya

Yup...... still on fire....
mavic2pro “awsome”

.....cR

 

[THE CYBORG]

please do not put your batteries in your freezer

Obviously I could be wrong but I was told by a battery expert that storing long term in a freezer ( on reflection this could be fridge ) was the best way as long as you wrap them and warm slowly to stop condensation forming.

Had a quick Google and came up with this.

 

[Nzporkdrone]

Speaking of batteries, is there a general time frame for the lifespan of a battery?? I’m guessing usage, temps and what not may alter the length of time a battery may last before it needs to be replaced. I don’t fly my mavic pro often at all. Am heading away this weekend so thought it would be a good time to charge the batteries and have a couple of quick flights before I take the drone away this weekend. 2 batteries charged up fine with the 3rd not wanting to charge. Infact the hub light turns red after a min or so. I try not to store the batteries fully charged. All 3 batteries came with the drone (fly more package) when it was brought new from the store back in late 2017 from memory.

 

[WithTheBirds]

The battery being transported at low temperature will have had no adverse effects. Storage below freezing (0deg C) will actually extend the life of LiION chemistry. Providing they are allowed to acclimatise before charging (charging below 0deg C will cause permanent damage) all will be good.

It is well known that DJI sources batteries from several manufacturers- it might be the cells have different makers with varying performance.

 

[old man mavic]

Obviously I could be wrong but I was told by a battery expert that storing long term in a freezer ( on reflection this could be fridge ) was the best way as long as you wrap them and warm slowly to stop condensation forming.

Had a quick Google and came up with this.

View attachment 80356

it is strange that keeping a battery very cold would increase its life span as we all know that very low temps reduce the amount of flight time maybe it works by inhibiting the chemical reaction from taking place inside the cell the only problem with keeping them in the freezer would be the possibility of ice forming in the cells and in the case of DJI batts damage to the electronics

 

[WithTheBirds]

it is strange that keeping a battery very cold would increase its life span as we all know that very low temps reduce the amount of flight time maybe it works by inhibiting the chemical reaction from taking place inside the cell the only problem with keeping them in the freezer would be the possibility of ice forming in the cells and in the case of DJI batts damage to the electronics

Chemical reactions are slowed at lower temps.

As to ice formation in the cells nothing in the electrolyte will freeze until below -30deg C. Domestic freezers won’t take you anywhere close to that point.

If the battery is placed in a sealed bag before it goes into the fridge and allowed to return to room temp before debagging there should be no effects on the electronics. Condensate formation should be absent or minimal.

 

[Deleted member 94047]

So much for my "insight", I guess I was wrong.