Battery discharging

[rene van der meer]

You're overthinking this. Just charge your batteries every time before you fly and Bob is your uncle

I fly mostly weekends. I have decreased the auto discharge to two days. On Friday I fully charge them. This is quite fast, because the battery is almost full.
Every 20 charges I do a full discharge (<10%).

 

[Keith Lampman]

I have this bulb battery discharger and it definitely works. It sure does get extremely hot though -- even after only running for a few seconds. You can discharge the battery down to a safe storage level or do a deep discharge. I like this discharger because it plays a sound when the discharge process has completed. The old version I had for my P2V+ just shut off when it was finished.

There is another type of battery discharger that runs a fan instead of lighting a bulb -- like this one. If anyone is concerned about the heat of the bulb, then it might be a better option.

On order from china
bulb battery discharger

 

[silvertonesx24]

Is it better to store the batteries discharged?

For example- in winter between light and weather I don't get out to fly too often. When I do, I will spend all of my batteries in flight, and unlike when I use any other camera gear and immediate charge up batteries I just spent when I get back, I keep Phantom batteries discharged until I know I am going out again.

Is this good practice, so I am not "wasting" cycles by filling them up right away and having them discharge?

 

[msinger]

Is it better to store the batteries discharged?

It's best to keep them between 30%-50% charged for long-term storage. If you press the battery button and only the first light illuminates, you should charge it up until the 3rd light starts flashing.

 

[rene van der meer]

It's best to keep them between 30%-50% charged for long-term storage. If you press the battery button and only the first light illuminates, you should charge it up until the 3 lights starts flashing.

silvertones24. You should not store a fully charged or a fully discharged LIPO for a longer period. This might shorten their lifespan dramatically.
Luckily we have intelligent batteries. You can charge them after a flight and rely on the auto discharge function to keep them in at optimal conditions.
This is why I have set the auto discharge time to 2 days. If I want to fly after that period I only have to recharge them to 100%. Which is wise anyway to do before a flight.

 

[Mark The Droner]

silvertones24. You should not store a fully charged ... LIPO for a longer period. This might shorten their lifespan dramatically.
..

Yes, but how would we do it? It seems almost impossible since the auto-discharge takes over. You'd have to store it at full charge and then purposely check/click the on button to disable the auto-discharge. And you'd have to do it over and over again - repeatedly - over the days/weeks that follow as if your goal is to purposely kill the battery.

Personally, I don't worry about my battery if it's at full charge. And I'm kinda **** about my batteries.

 

[rene van der meer]

Yes, but how would we do it? It seems almost impossible since the auto-discharge takes over. You'd have to store it at full charge and then purposely check/click the on button to disable the auto-discharge. And you'd have to do it over and over again - repeatedly - over the days/weeks that follow as if your goal is to purposely kill the battery.

Personally, I don't worry about my battery if it's at full charge. And I'm kinda **** about my batteries.

I don't mind that the batteries discharge automatically. Before the weekend I recharge the batteries. Then I am sure there are 100%.
If the weather doesn't allow flying I don't have to worry about the batteries.

 

[FredzMaxxUAV]

The automatic discharging works fine, to 2 LEDs. But I notice that after a week or more it goes down to 1.5 LEDs and then even less. Is this a problem? As I thought that ideally you'd store a LiPO at about 50%.

 

[Wacker2611]

Mine are on 10 days, so I usually manage by batteries manually. 2 led's constant, 3rd one flashing works for me. I tend to charge and go anyway - I will rarely have charged batteries laying about, the fresher the charge the better. It only takes roughly 30 mins to charge a storage state battery anyway, even with the p3a weedy charger.

 

[Solar Deity]

The automatic discharging works fine, to 2 LEDs. But I notice that after a week or more it goes down to 1.5 LEDs and then even less. Is this a problem? As I thought that ideally you'd store a LiPO at about 50%.

3.85V/Cell is a great storage/shipping charge for Lipos.

SD

 

[FredzMaxxUAV]

Yes but after a while they discharge further, don't they, going to 1.5 LEDs, 1 LED, 0.5 LED. Isn't that bad for the battery?

 

[Solar Deity]

Yes but after a while they discharge further, don't they, going to 1.5 LEDs, 1 LED, 0.5 LED. Isn't that bad for the battery?

Yes, it would be bad to over discharge past 3.0V/Cell. I never checked the voltage with the lesser LED's lit.

SD

 

[Mark The Droner]

The automatic discharging works fine, to 2 LEDs. But I notice that after a week or more it goes down to 1.5 LEDs and then even less. Is this a problem? As I thought that ideally you'd store a LiPO at about 50%.

Yes but after a while they discharge further, don't they, going to 1.5 LEDs, 1 LED, 0.5 LED. Isn't that bad for the battery?

My understanding and IIRC, the perfect storage charge per the manual is 40-50% (or around 3.85 v per cell as mentioned by SD above). So if your battery auto-discharges to 40% and shows 1.5 LEDS, it should be fine. It shouldn't auto-discharge lower than that. The "intelligent" software in the battery should stop the auto-discharge when it reaches that point. If you don't trust it, you can check the actual percentage with your own software app. If your battery is auto-discharging lower than about 40%, then it seems you've got a problem with that battery.

 

[msinger]

the perfect storage charge per the manual is 40-50%

DJI recommends storing the battery between 30-50% charged. I'm assuming up to 65% is acceptable to them though since that's where they programmed their auto discharge feature to stop.

So if your battery auto-discharges to 40% and shows 1.5 LEDS, it should be fine. It shouldn't auto-discharge lower than that. The "intelligent" software in the battery should stop the auto-discharge when it reaches that point.

The battery will only auto discharge to 65%.

It shouldn't auto-discharge lower than that.

The auto discharge feature won't continue below 65%, but the battery will naturally discharge beyond that over time.

 

[Mark The Droner]

Okay. My Vision manual says store at 40-50% and I assumed it would be the same. My bad.

 

[msinger]

My Vision manual says store at 40-50%

I found the DJI battery safety guidelines to be the best source of information on this topic.

 

[Mark The Droner]

That is a lot of good specific info in that link. And some of the vagueness that are in other DJI battery info sources seems to be addressed. I've read my Vision manual word for word like 5x, but I like this document just for its clarity. Batteries are so very important. A bad battery can kill your aircraft. I suggest everybody reading this thread to read the info in the above link.

Some points:

Battery should be used in temps from -10C to 40C.

That's 14F to 104F. Do you think they mean the temp of the battery or the temp of the flying environment? I'm going to guess the flying environment since we all know not to fly with cold batteries.

Ideal storage temp is 22C - 28C.

That's 72F to 82F. In other words, room temp. No storing batteries in the 'fridge or the back shed.

During deep discharge, charge the battery until there is 8% remaining power...

Okay. My Vision manual says "below 8%" and my ebay discharger takes it down to 3%. No issues so far.

Discharge the battery to 30-50% if it will not be used for 7 days or more. This will greatly extend battery life.

Check. So do we think this means we should not rely on the auto-discharger and should be more pro-active in discharging when not flying for more than a week? - Especially since we know the auto-discharge stops at 65%?

 

[msinger]

That's 14F to 104F. Do you think they mean the temp of the battery or the temp of the flying environment?

The flying environment.

So do we think this means we should not rely on the auto-discharger and should be more pro-active in discharging when not flying for more than a week? - Especially since we know the auto-discharge stops at 65%?

I think this means it's okay to store batteries between 30%-65% charged. Otherwise, DJI would have made that function discharge the battery to 50%.

 

[David Cohran]

So we are suppose to discharge our batteries? How about the RC?

 

[Tuomo Björksten]

Some points:

Battery should be used in temps from -10C to 40C.

That's 14F to 104F. Do you think they mean the temp of the battery or the temp of the flying environment? I'm going to guess the flying environment since we all know not to fly with cold batteries.

However, P3P works well even in -27 C (I've tried). You just have to be very careful, not fly too long and keep the batteries warm.