Batteries - the basics?

[Proud_Hufflepuff]

Hi all

I've been reading a lot about battery care and it's all a bit confusing....

As I understand it I shouldn't be storing them fully charged for longer than 24 hours.

I should store them between 30% and 60%(?), and only fully charge the day before I fly.

They need to be discharged to around 10% and then fully charged every 10 charges.

So if I flew to a low battery warning yesterday and I'll not be flying for a few day I should charge the battery tonight until 30-60%? Can you tell by lights what % a battery is roughly or do you need to put it in the phantom and use the app?

Sorry for all the questions but I want to get into good battery habits straight away.

Also is a fireproof case a good idea for battery storage?

 

[msinger]

I should store them between 30% and 60%(?), and only fully charge the day before I fly.

That would be best.

They need to be discharged to around 10% and then fully charged every 10 charges.

That is what's known as cycling the batteries. It's not necessary. Just make sure you use your batteries at least once every three months.

Can you tell by lights what % a battery is roughly or do you need to put it in the phantom and use the app?

Yes. Check out this post.

is a fireproof case a good idea for battery storage?

Necessary? No. The batteries likely won't catch on fire. I don't take any chances those since I store my batteries in my house. I keep them in these HOBBYTIGER LiPo bags.

 

[Proud_Hufflepuff]

That would be best.


That is what's known as cycling the batteries. It's not necessary. Just make sure you use your batteries at least once every three months.


Yes. Check out this post.


Necessary? No. The batteries likely won't catch on fire. I don't take any chances those since I store my batteries in my house. I keep them in these HOBBYTIGER LiPo bags.

So essentially I should charge mine back up until the 3rd light is blinking.

What's the Auto Discharge thing the post mentions?

 

[solentlife]

Ok ... lets go point by point ...

"Hi all

I've been reading a lot about battery care and it's all a bit confusing...."

Yes - particularly that DJI themselves don't even get ir right !!

"As I understand it I shouldn't be storing them fully charged for longer than 24 hours."

True - in fact the least time at full charge the better.

"I should store them between 30% and 60%(?), and only fully charge the day before I fly. "

In fact the 60% is absolute max you should ever store at ... its much better to be at the 30% mark. Recc'd storage voltage is from 3.7 to 3.85V per cell.
Best is to charge up just before you fly to ensure you have max charge for your flight. Try to avopid getting into what is termed 'top-up habit' ... where people charge up day or so before .. then put back on charge just before flying ... it does no good for the battery.

"They need to be discharged to around 10% and then fully charged every 10 charges."

No way ... even DJI have given up that myth. All you do is use up life and it has no beneficial effect at all. It is also reported that it 'resets' the mAh capacity counter ... well I can say without any doubt that is a crock of **** !. People attribute that because of so-called increased numbers in the Go app battery display. In fact all it is really is an estimated capacity based on detected voltage.

"So if I flew to a low battery warning yesterday and I'll not be flying for a few day I should charge the battery tonight until 30-60%?"

As long as the total battery voltage is not below 14.8V or above max 15.4V ... you are fine to leave batterys alone after flight. I never partial charge after flight and I usually land at about 30% ... which once rested bounces back to about 35%.

"Can you tell by lights what % a battery is roughly or do you need to put it in the phantom and use the app?"

Yes you can by reading the number of solid LED's and flashing LED"s - but its a very crude way of doing it. Best is a Multi-Meter on the main contacts with battery switched on ...

"Sorry for all the questions but I want to get into good battery habits straight away."

Excellent .... wish everyone did same ! One thing you can do now - is to change the Auto-Discharge time on your batterys. DJI set a 10day auto-discharge to the batterys. This is far too long. It is recc'd to reset that to 1, 2 or max 3 days. This means that if you charge up a battery or only fly it partially. While it sits quiot not in use, a timer will cut in at set time and start automatically discharging battery to storage level. There is no need for you to worry about this. But if you pick up that battery and start pressing button - the timer will reset and start all over again.

"Also is a fireproof case a good idea for battery storage?"

All LiPo batterys have potential for Thermal Runaway ... that is fire that is self sustaining and difficult to extinguish. Usually only occurs with mistreatment, over charging or damage... A rare but not unknown occurrence.
Fireproof case ? Some people use Ammo Cans ... some people use LiPo sacks. The ammo cans require a small vent and should not be sealed tight.
LiPo Sacks are NOT fire-proof ... NONE ARE ! They are Fire Resistant only and allow you possibly time to throw the lot out the window or put to a safe place to let it burn out. Many in fact are barely resistant and give false sense of safety. Youtube has many videos to support my statement here.
I have 4 LiPo sacks .... 3 are just ordinary LiPo safe bags and 4th is the Hobby King Heated bag for use in winter. I carry all inside a large picnic foil lined cooler bag. This adds to the time factor I have to move the lot because of the foil lining.

LiPo's just demand respect and care.

Good luck
Nigel

 

[msinger]

So essentially I should charge mine back up until the 3rd light is blinking.

Yes, but it's only necessary when the battery drops below about 30%. Press the battery button once to check the charge. If the second light is not solid or blinking, then you should charge the battery.

What's the Auto Discharge thing the post mentions?

The battery will start to auto discharge down to about 60% after it has not been used for the number of days set in the "Time to Discharge" setting in DJI GO (see the screenshot below). It'll take an additional 2-3 days for the battery to discharge (when fully charged) once it starts discharging. If you press the battery button, the battery will stop auto discharging and/or the time to discharge counter will be reset. So, you shouldn't keep pressing the battery button to check if it's discharging. It'll never discharge if you do that.

Note: The "Time to Discharge" setting needs to be set for each battery while your Phantom is connected to DJI GO. You'll need to reset that setting each time new firmware is installed on the battery.

 

[solentlife]

Discharge - the auto-discharge is often said to be 60% ... sorry but not actually correct.

The Battery Safe Guidelines say to below 65% from the set time.... about 3days.

But lets not split hairs !! Because 60% itself is really too high a level for long term. Its much better at the 30 - 40% level ... which is 1 LED solid and 2nd LED blinking or at most solid. I suggest not to go above 2 solid LED level which is 50%.

What is interesting - in tests - we confirmed that discharge does not actually stop at the 65% but just slows to an idle pace and discharge continues until it reaches the 'Hibernation state' of much lower. I found this at 35% ... others at other levels but similar.

I have noticed that some questions have arisen about the lack of LED lights to show battery state after long term storage. If the RED LED comes on but no GREEN - then this is the reason. Battery has entered 'Hibernation'. To awaken the battery leave it switched on with RED LED on and after about 5 mins - it should go out. Then connect to charger and it will 'wake up' .... Bit of info that really most will never use ... but useful to know.

I appreciate that I may be at odds with some people about these batterys, but it appears that repeated 'myths' have become accepted as fact, which in my opinion is about time to dispel and correct. Many new people are joining the Quad / DJI world and its worth them having reasonably accurate info.

Nigel

 

[N42742]

Here's what a battery fire looks like:

https://fpdl.vimeocdn.com/vimeo-pro...19-0x4b5fced328beb9096c082d122dcd5f11407e2074

 

[solentlife]

LiPo sacks :

Why does ammo can need a vent ? Watch this ...

Nigel

 

[Proud_Hufflepuff]

Would a large cash box be a suitable alternative to an ammo box?

Something like this?

 

[solentlife]

I am now going to amaze and stupify many ...

I have plastic Ice Cream containers lined up on the lower shelf of my charger bench. Each has a designated range size of LiPo in.
My bank of chargers sit on the top shelf of the bench with power supplied.

All batterys sit at storage level in those containers except my DJI which stay in the backpack case I have.

When I go flying : Standard lipo's go in my LiPo sacks ... being 3 of them - each takes a different size as with my storage. The sacks then placed into my Cooler bag. DJI stay in my Phantom carry case.

There are levels of LiPo care across the board ...

Some people say they never charge indoors and do it on concrete slab outside.

Some say they place LiPo in ceramic pot for charging

Some like me just charge indoors clearly visible and next to window where it can be 'jettisoned'

Some store in sealed Ammo Boxes

Some store in Fire-Resistant cash boxes

Some just store on a shelf

Some store as I do

Funny thing is ... I have not seen a report of a SHOP fire caused by LiPo when they are often on view under / behind glass or on shelf .... I know of shop fires - but LiPo was not the cause.

The decision of what is done is down to the individual. But there are two extremely important items to keep in mind :

1. NEVER overcharge or attempt to charge LiPo with unsuitable charger. If charger is faulty - DON'T USE IT !

2. Don't puncture / cut / open up or interfere with the internal foil envelope of each cell. You can open the case / plastic surround if a wire has come adrift to fix but NEVER try to get into the cell !! If a LiPo is damaged in a crash ... DISPOSE of it properly.

Nigel

 

[N017RW]

I have said for years I store LiPos like my local hobby shops store the hundreds they have in-store.
On a shelf.
LiPos are not time-bombs. In the 11 or so years I have been using them never had any problems.
DJI makes no mention of exotic storage and only say do not leave them unattended during charging.

 

[That Cicero Guy]

I use DJI's charging hub for my Phantom 4 Pro batteries. It's powered by the standard charger and has a storage mode button you switch to so when you aren't using the batteries, it charges or discharges them automatically to 50% and keeps them there until you flip the switch back to charging mode before you fly. It works very well.

DJI Phantom 4 Intelligent Battery Charging Hub, White (6958265112836) Amazon.com : DJI Phantom 4 Intelligent Battery Charging Hub, White (6958265112836) : Camera & Photo

 

[Randyg08]

How many flights are most of you getting out of a well maintained battery?