Battery does not hold charge

[Conde]

I have 3 batteries with less than 20 flights each and not hold a charge
with full load, only fly 1 minute and the battery charge drops drastically
Someone could help me?
Thank you in advance

 

[RoyVa]

Put battery in question in your Phantom and hook up to the assistant and go to the battery tab and see what info it gives. If their is a large variation between cells you may have a damaged or bad battery. Look at the percent of charge and especially the percent of life. The cell voltage should be fairly close to each other within about 100 mV is good. Do you see any puffiness on the sides of the battery?

 

[yorlik]

conde, i am curious: when you flew when batts were still good, how low did you fly them? i mean, what was typical charge after each flight when they wee still ok?

after charge, do all 4 lites lite?

 

[Conde]

Put battery in question in your Phantom and hook up to the assistant and go to the battery tab and see what info it gives. If their is a large variation between cells you may have a damaged or bad battery. Look at the percent of charge and especially the percent of life. The cell voltage should be fairly close to each other within about 100 mV is good. Do you see any puffiness on the sides of the battery?

Yes, I see little puffines on the sides.

 

[Conde]

conde, i am curious: when you flew when batts were still good, how low did you fly them? i mean, what was typical charge after each flight when they wee still ok?

after charge, do all 4 lites lite?

100% charged is discharged in 2 minutes; have 100% battery life

 

[Karanba]

They should be charged BEFORE the flight, not right AFTER the last flight. Basicaly you should leave them with that 30% charge and store, then when you want to go fly, charge them. Imagine that you charge them with mineral water with bubbles No sense in filling it 3 days before the flight but right before

 

[yorlik]

Put battery in question in your Phantom and hook up to the assistant and go to the battery tab and see what info it gives. If their is a large variation between cells you may have a damaged or bad battery. Look at the percent of charge and especially the percent of life. The cell voltage should be fairly close to each other within about 100 mV is good. Do you see any puffiness on the sides of the battery?

Good points of course.

For comparison, I have a donated battery for testing that says "bad cell" with just 30mv difference. Both my good batts are always within about 10mv of each other all the time....

Know that "battery life" means nothing useful: it is a simple mathematical calculation not based on battery performance or capacity. It is simply 100*(300-cycles)/300 answer in percent, 'cycles' is the value shown in assistant as number of charge cycles used.

 

[yorlik]

100% charged is discharged in 2 minutes; have 100% battery life

For "100% life" the battery must be new with 0 charge cycles. Do you show any charge cycles? Is so, then your battery has Alzheimer's and probably will not recover (ie., internal memory garbage).

 

[jonnied]

yorlik, I'm glad to see you are still with us on the battery issues.
In all of your testing have you figured out what data is being transferred to the Phantom from the two data pads on the battery?
The reason I ask is because I sometimes get a message while flying "Invalid Battery". I have four batteries that are all healthy but this is a random notice that pops up and disappears.
Yesterday I placed a battery into the Phantom while connected to the computer with DJI Phantom 2 Vision Assistant_3.8 running and a message came up stating "Battery not an intelligent Dji battery".
The battery info screen would not show any information on the battery.
I restarted the software and phantom several times and finally got the battery to respond.
Contacts on the battery and Phantom are cleaned often wit a q-tip and contact cleaner.

Battery info:
Purchase Date:3/2/2015
#1
Charge at time of check:36%
Full Capacity
5485mAh
Discharge times 15

Purchase Date:3/2/2015
#2
Charge at time of check:36%
Full Capacity
5473mAh
Discharge times 16

Purchase Date:5/20/2015
#3
Charge at time of check:31%
Full Capacity
5506mAh
Discharge times 6

Purchase Date:5/20/2015
#4
Charge at time of check:33%
Full Capacity
5463mAh
Discharge times 7
I will start another post showing screen shots of my battery errors during flight with o few more questions?

 

[yorlik]

johnied, no clue; never dug into the serial data string. I bet your batteries, like mine, have never been subjected to the "discharge to 8%" routine - maybe why we both show higher than new full capacity. You probably only fly down to like 40% min too? Maybe 30% on rare occassions? Mine still show 5300-5450 full capacity with 30+ cycles. I am ok with it since it means I do not get caught in the artificial quick % charge dropping in seconds issue that gets folks in trouble (knock on wood).

I had one fake "invalid battery" one time a year ago when powering back up after a flight to download the SD card pix; power cycle and it went away... Although as a ham and engineer, I have spray bottles of contact cleaner, and use it on volume controls often enough and after pcb repairs, I have never cleaned my batt or pv2+ batt mate contacts.

 

[jonnied]

I strive to land above 40%. I also use a THUNDER POWER TP610C to charge the batteries, and only charge at 1 Amp, not 1C like the stock charger.

 

[yorlik]

me too - that way we get TWO smart shut offs in case 1 tries to charge a tad too high and harm the battery a tad! But my ICE charger won't let me do 1amp! it times out before finish, so I charge at 2 amps and MY charger actually pulls the plug BEFORE the dji every time - good indication to me that the dji might charge a tad too long. If my charger was smarter, I would even set the CV final charge down to 11.1v instead of 11.2 and accept only a 90% full charge to help extend the battery - probably double again. Bet you and I will approach the 300 cycle design life that no one else ever has hit!

I tend to land at 40-50% too. That is enough time to go my farthest comfy distance of like 1000 feet a few times, or the length of the longest GPS route I have had guts to try to date.

My 35kwh 350vdc full EV conversion car had like new batteries when I sold it back to the builder 4 years after I got it. Course I DID work closely with the BMS controller folks and showed them a few improvements and bug fixes they needed to make.

 

[jonnied]

me too - that way we get TWO smart shut offs in case 1 tries to charge a tad too high and harm the battery a tad! But my ICE charger won't let me do 1amp! it times out before finish, so I charge at 2 amps and MY charger actually pulls the plug BEFORE the dji every time - good indication to me that the dji might charge a tad too long. If my charger was smarter, I would even set the CV final charge down to 11.1v instead of 11.2 and accept only a 90% full charge to help extend the battery - probably double again. Bet you and I will approach the 300 cycle design life that no one else ever has hit!

I tend to land at 40-50% too. That is enough time to go my farthest comfy distance of like 1000 feet a few times, or the length of the longest GPS route I have had guts to try to date.

My 35kwh 350vdc full EV conversion car had like new batteries when I sold it back to the builder 4 years after I got it. Course I DID work closely with the BMS controller folks and showed them a few improvements and bug fixes they needed to make.

yorlik
Have you measured a small amount of drain in the smart board while the batteries are powered off? My DJI batteries seem to drain more in storage than my other lipos. I put them away at around 45% to 50% and find that after awhile they will be down into the 30% to 35% range if not used in 2 or 3 months. I think if you don't keep an eye on them they can actually get too low. I give them a boost to storage charge levels once and a while. You can see what they were down to in my info above. Did you ever find out where the self discharge cuts off at? I wonder if it kicks in even if the batteries are at around 50% weather it needs to or not.

 

[yorlik]

never bothered measuring batt current out of drone.... so I just measured current thru the main batt terminals from cells to the pcb:

0 with batt OFF
20ua batt ON

So n current THAT path.... I do not have easy (lazy) way to check current thru the cell balance connector brom cell board to main pcb, so I just stuck it on crooked: 2ua from one cell balance line to main pcb.... so if assume other 2 also are 2ua, thats 6ua total....

means effectively zero discharge sitting in our flame proof ammo boxes between uses. This test batter was 50% charge about 4 months ago, and is still today. I think the lipo cells will self discharge faster than the ua current draw of the smart battery when off....

I really doubt the cells drop by software beyond that discharge to 50-60% routine after 10 days once time, but no proof other than mine seem to stay exactly the same mah remaining when checked weeks after last use....

 

[yorlik]

Are you going to upgrade to P3 or P4? I see no reason to with the FAA and everyone else sticking their regulations on us. I can live with my P2 forever I think....

 

[jonnied]

never bothered measuring batt current out of drone.... so I just measured current thru the main batt terminals from cells to the pcb:

0 with batt OFF
20ua batt ON

So n current THAT path.... I do not have easy (lazy) way to check current thru the cell balance connector brom cell board to main pcb, so I just stuck it on crooked: 2ua from one cell balance line to main pcb.... so if assume other 2 also are 2ua, thats 6ua total....

means effectively zero discharge sitting in our flame proof ammo boxes between uses. This test batter was 50% charge about 4 months ago, and is still today. I think the lipo cells will self discharge faster than the ua current draw of the smart battery when off....

I really doubt the cells drop by software beyond that discharge to 50-60% routine after 10 days once time, but no proof other than mine seem to stay exactly the same mah remaining when checked weeks after last use....

Thanks yorlik, I'll watch and see. my batteries had been setting for some months when I checked them the last time.