BATTERY ISSUES (Early Autoland)??? POST HERE

[6600RPM]

I had an incident a few weeks ago that got my attention when my P2 autolanded at 30% of battery capacity. This is not as bad as some as some of you have reported, but it concerned me because I was not expecting my P2 to autoland until I was at or around 15%.

Yesterday, took my 6 batteries out for a thorough test. I am on firmware update 3.04. Warning levels are set at 30% and 15%. My P2 is configured for FPV, including a Polar Pro ND filter and counterweights, and weighs in at a heavy 1385 grams.

My oldest battery, with 33 discharges, was the battery that caused my autolanding at 30% my last time out. It was completely discharged after the 20th discharge and appeared to function normally until my last flight. My other batteries range from 27 to 4 discharges.

Before yesterday's test, I completely charged all six batteries so that they would be as full as possible for the test.

Resutls:
My #1 (oldest) battery with 33 discharges autolanded at 26% with 10.7 volts remaining.

My other batteries autolanded as follows:

#2 with 27 discharges autolanded at 13% and 10.8 volts remaining
#3 with 17 discharges autolanded at 13% and 10.8 volts remaining
#4 with 11 discharges autolanded at 14% and 10.8 volts remaining
#5 with 11 discharges autolanded at 13% and 10.8 volts remaining
#6 with 4 discharges autolanded at 12% and 10.8 volts remaining

From this test, It appears that my P2 triggers an autolanding when the battery reaches 10.8 volts, not withstanding the % of battery capacity that the iOSD displays. My guess is that 15% of capacity and 10.8 volts remaining coincide for a healthy battery, but we are obviously seeing some variation.

My takeaway from this test is to pay attention to remaining battery voltage rather than % of battery capacity.

 

[wkf94025]

See my post in this thread on June 22nd, 10am. I suspect you are hitting the 10.67v hidden trigger pointed out by ElGuano, and in the firmware release notes from v1.05 or thereabouts last fall. Was your flying super steady in terms of battery drain, or were there rapid climbs or other exertions that could cause the battery to sag for a few seconds below 10.67v? Remember iOSD is almost certainly rounding, so 10.67v will read as 10.7v in iOSD.

I think a characteristic of an "aging" battery is that it hits 10.67v well before it hits 15%.

Kelly

 

[6600RPM]

See my post in this thread on June 22nd, 10am. I suspect you are hitting the 10.67v hidden trigger pointed out by ElGuano, and in the firmware release notes from v1.05 or thereabouts last fall. Was your flying super steady in terms of battery drain, or were there rapid climbs or other exertions that could cause the battery to sag for a few seconds below 10.67v? Remember iOSD is almost certainly rounding, so 10.67v will read as 10.7v in iOSD.

I think a characteristic of an "aging" battery is that it hits 10.67v well before it hits 15%.

Kelly

Because my objective is video photography and my P2 is overweight, I try to fly as smoothly as possible -- no rapid climbs.

Thanks for the info re: the 10.67v hidden trigger. Looks like I need to keep my eye on one aging battery.

 

[macheung]

I noticed that my p2 also seems to skip the 1st warning stage set at 25% and goes straight into autoland mode. Though I did not thought much of it as I brought it close for landing anyway, will keep a log of details here next time.

If this happens, most have squad that they can override it eith 90% throttle! but what happens if it was on RTH mode? Will it keep trying to reach home or will it autoland wherever it is? In other word, what wins, RTH and land, or low battery land now?

 

[shartlza]

Overall it really sounds like these batteries loose their juice pretty quickly after not too many uses, which is very disappointing for a battery that cost $159!!!

Macheung, Autoland will override RTH. So if it does this during a RTH you better hope you can see it and try the override RTH and give it full throttle up and full forward to get it back to you or you will be SOL.

 

[Double-D]

Overall it really sounds like these batteries loose their juice pretty quickly after not too many uses, which is very disappointing for a battery that cost $159!!!

Macheung, Autoland will override RTH. So if it does this during a RTH you better hope you can see it and try the override RTH and give it full throttle up and full forward to get it back to you or you will be SOL.

Indeed it will.
Point camera down and find a place to land.....or sink

 

[WessexWyvern]

I had an incident a few weeks ago that got my attention when my P2 autolanded at 30% of battery capacity. This is not as bad as some as some of you have reported, but it concerned me because I was not expecting my P2 to autoland until I was at or around 15%.

Yesterday, took my 6 batteries out for a thorough test. I am on firmware update 3.04. Warning levels are set at 30% and 15%. My P2 is configured for FPV, including a Polar Pro ND filter and counterweights, and weighs in at a heavy 1385 grams.

My oldest battery, with 33 discharges, was the battery that caused my autolanding at 30% my last time out. It was completely discharged after the 20th discharge and appeared to function normally until my last flight. My other batteries range from 27 to 4 discharges.

Before yesterday's test, I completely charged all six batteries so that they would be as full as possible for the test.

Resutls:
My #1 (oldest) battery with 33 discharges autolanded at 26% with 10.7 volts remaining.

My other batteries autolanded as follows:

#2 with 27 discharges autolanded at 13% and 10.8 volts remaining
#3 with 17 discharges autolanded at 13% and 10.8 volts remaining
#4 with 11 discharges autolanded at 14% and 10.8 volts remaining
#5 with 11 discharges autolanded at 13% and 10.8 volts remaining
#6 with 4 discharges autolanded at 12% and 10.8 volts remaining

From this test, It appears that my P2 triggers an autolanding when the battery reaches 10.8 volts, not withstanding the % of battery capacity that the iOSD displays. My guess is that 15% of capacity and 10.8 volts remaining coincide for a healthy battery, but we are obviously seeing some variation.

My takeaway from this test is to pay attention to remaining battery voltage rather than % of battery capacity.

That's very interesting, I'll see if I get the same results when I get a chance. Thanks for posting

 

[N017RW]

I recently upgraded my control to a Futaba T10J and 3008SB Rx.

The test battery has 17 flights with most discharged to about two LEDs.

I have recently connected the on-board external battery telemetry port on the Rx and have noticed it does auto-land at 10.8v indicated.

I do not have 'percentage left' data other than when I have run till auto-land it has one solid LED.

I posted this to further indicate or bolster the 10.8v landing threshold theory.

Despite the 10.8v indicated at the Rx it may well be 10.65 when measured by the battery's 'smart' circuitry.
A difference in 'under load' DCV readings does not surprise me.

 

[wkf94025]

Thanks for the info re: the 10.67v hidden trigger. Looks like I need to keep my eye on one aging battery.

Here is an excerpt from a flight in late May where I first experienced premature auto-landing. Fortunately I was a long ways from the ocean.

--------------------------------
My Garmin GTU-10 just paid for itself today. I was almost 4km out and thought I had more tail wind coming home than I did. At some point the battery level dropped to the point where I saw something in the lower left corner of OSD that I'd never seen before: "LAND". I assume that was the "below 15% battery so better to land here/now than fall out of the sky" algorithm kicking in. So I knew I was going down, and tilted camera straight down looking for best ditch options. I managed to avoid a swimming pool and several very tall oak trees, and reposition over a vineyard. (Vineyards make for good/great ditch spots because if you're lucky you tangle up in the trellis wires or vine shoots and actually never impact terra firma.) Then I realized the P2 was sufficiently high that it might lose all power and drop before its leisurely self-land algorithm brought it down. So I pulled down hard on left stick, trying to move upwind to avoid VRS. No cigar however, as I was soon dropping at rates I'd never seen before. I figured all was lost but kept trying to fly out of the downshaft and regain clean air. At that point FPV became unusable (~20m altitude with me ~2km away), and I thought I would have a very hard landing. I threw everything in the truck and started driving toward the ditch point, checking the Garmin app on my android phone. It worked perfectly in helping me locate my quad, which (upon video replay) had a fairly gentle landing -- after VRS recovery at a fairly low altitude -- in the vineyard trellis wires. The motors continued running and eventually drained the battery. I arrive some 10 min later and found an exhausted but intact P2. Only damage was lots of green stains on props from the grape leaves. Threw out all four for a new set, and did deep IMU calibration.
-------------------------------

I now believe this was the 10.67v hidden trigger, during RTH. Be forewarned when wandering far from home on an older battery.

Kelly

 

[Zinnware]

Autoland at 92%
I guess I am the latest victim to a bad battery. Mine will go into autoland just as it reaches 92% or about 1 to 2 minutes of hovering. I have a video that shows the battery level indicator go from full charge to zero from the DJI osd mini.
http://youtu.be/K8YaDtoFVi4

[youtube]http://www.youtube.com/watch?v=K8YaDtoFVi4[/youtube]

 

[MrC]

Zinnware, the pic of the assistant where it says 99% charged, it says 11.8v overall and 3.9v for each cell. A fully charged 3s lipo should be at 12.6v and each cell at 4.2v. Assuming you didn't have the motors fired up when you took the pic of the assistant. (v will drop under load). 3.9v is about 40% charged.

Have you done the complete discharge to <8% and recharge procedure?

 

[Zinnware]

Zinnware, Have you done the complete discharge to <8% and recharge procedure?

Yes. Handwritten on the battery end is a number 47%. On the previous flight it cut out at 47% and then I ran the battery down to 7% to make sure it was discharged. On this flight it cut out at 92% b just hovering. I just ran it down to below 8% again and will recharge and post an additional screen shot from the Assistant software.

Update: The two screen shots below show the Assistant screen before and after the video was taken.

 

[Zinnware]

As a follow-up to my previous post. I recharged the battery last night and took the screen shot. See the previous post. Tonight I took it for another flight. At 92% again the phantom experienced the battery level indicator flashing and empty on the OSD just like the condition seen in the previously posted video. The phantom green lights switched to the rapid flashing lights again too. I took it down and hovered. The green lights came back. I gave it full throttle up and immediately is switched back to the flashing battery icon and the red flashing lights. I repeated this action of hovering until the red flashing rear lights switched back to green and then giving full throttle up a low altitude (5 to 30 feet). Any time I put load on the motors the low empty battery icon would flash. This continued until after just a few minutes the battery percentage reached 71%. At that point the red lights stayed on and I countered the auto landing bu giving it an up throttle to stabilize the altitude at about 1 meter. The battery percentage during the phase dropped a percentage about every 2 to 3 seconds until it reached 0% in a few minutes. The voltage reading varied between 10.8V and 11.2 volts. I truly believe that this battery is faulty.
Attached is a screen shot after the mission.

Thoughts?

 

[shartlza]

As a follow-up to my previous post. I recharged the battery last night and took the screen shot. See the previous post. Tonight I took it for another flight. At 92% again the phantom experienced the battery level indicator flashing and empty on the OSD just like the condition seen in the previously posted video. The phantom green lights switched to the rapid flashing lights again too. I took it down and hovered. The green lights came back. I gave it full throttle up and immediately is switched back to the flashing battery icon and the red flashing lights. I repeated this action of hovering until the red flashing rear lights switched back to green and then giving full throttle up a low altitude (5 to 30 feet). Any time I put load on the motors the low empty battery icon would flash. This continued until after just a few minutes the battery percentage reached 71%. At that point the red lights stayed on and I countered the auto landing bu giving it an up throttle to stabilize the altitude at about 1 meter. The battery percentage during the phase dropped a percentage about every 2 to 3 seconds until it reached 0% in a few minutes. The voltage reading varied between 10.8V and 11.2 volts. I truly believe that this battery is faulty.
Attached is a screen shot after the mission.

Thoughts?

Your battery is absolutely faulty. I would contact your dealer or contact DJI. From all the people that have posted about this issue it really looks like all of these are battery issue and most people are getting them replaced through their dealer or through DJI. I myself just got a tracking number from DJI today and my new battery will be here Monday.

 

[Double-D]

As a follow-up to my previous post. I recharged the battery last night and took the screen shot. See the previous post. Tonight I took it for another flight. At 92% again the phantom experienced the battery level indicator flashing and empty on the OSD just like the condition seen in the previously posted video. The phantom green lights switched to the rapid flashing lights again too. I took it down and hovered. The green lights came back. I gave it full throttle up and immediately is switched back to the flashing battery icon and the red flashing lights. I repeated this action of hovering until the red flashing rear lights switched back to green and then giving full throttle up a low altitude (5 to 30 feet). Any time I put load on the motors the low empty battery icon would flash. This continued until after just a few minutes the battery percentage reached 71%. At that point the red lights stayed on and I countered the auto landing bu giving it an up throttle to stabilize the altitude at about 1 meter. The battery percentage during the phase dropped a percentage about every 2 to 3 seconds until it reached 0% in a few minutes. The voltage reading varied between 10.8V and 11.2 volts. I truly believe that this battery is faulty.
Attached is a screen shot after the mission.

Thoughts?

Your battery behaves exactly as mine did including the 100mV difference in cell 2.
My warranty claim was approved no questions asked, sent back to my dealer and now just waiting for replacement stock.

 

[Outtahere100]

Just got off the phone with DJI in Los Angeles. I got an RMA number for two batteries that exhibit the same symptoms that others have described on this thread. Both of my batteries are the older style, with the small contact pads. Has anyone had the newer style battery fail?

John (grounded until replacement batts arrive)

 

[shartlza]

Just got off the phone with DJI in Los Angeles. I got an RMA number for two batteries that exhibit the same symptoms that others have described on this thread. Both of my batteries are the older style, with the small contact pads. Has anyone had the newer style battery fail?

John (grounded until replacement batts arrive)

I don't know if the smaller contacts on the old battery are to blame or if those are just the older more used batteries. I hope it is not the older battery that has the issue because i just got my replacement battery from DJI in LA and it was the older one with the small contact pads. :? I guess i will find out in abot 70 discharges. :|

 

[Double-D]

Just got off the phone with DJI in Los Angeles. I got an RMA number for two batteries that exhibit the same symptoms that others have described on this thread. Both of my batteries are the older style, with the small contact pads. Has anyone had the newer style battery fail?

John (grounded until replacement batts arrive)

I don't know if the smaller contacts on the old battery are to blame or if those are just the older more used batteries. I hope it is not the older battery that has the issue because i just got my replacement battery from DJI in LA and it was the older one with the small contact pads. :? I guess i will find out in abot 70 discharges. :|

That's if they make it to 70 cycles. Mine only made it to 20+

 

[J.James]

i have one of the ones with the small pads on it and it was faulty from the get go and never ever charged right and had a dead cell in it. and its not the pads and is an internal problem with the so called smart battery part of it.

The pads on the other hand are what cause it to also have the false non dji battery thing happen which is entirely a different issue all together with the battery and the phantom 2. And its not due to the size of the pads or how wide they are as much as it is to do with the pins that connect to it only sticking out about 1/32th to 1/64th of an inch further then the point of when they first touch when the battery is being seated to when its all the way in and cant be pushed in any farther. So in other words there just is hardly any contact pressure at all because the springs on the 2 pins are just barely able to contact the battery when its pushed all the way in and even when they do 1 64th of an inch compression on them pins is hardly any pressure at all and if the battery wiggles back any bit at all they cam lose contact. If them pads were made to stick out even just a tiny bit more on a redesigned battery would help prevent that. and if they got rid of the internal not so smart charging circuit in side the battery's would also help prevent the other problem of the cells not being charged right and not balancing the cells. Even if they just added a balance lead to them it would let some one be able to use a separate charger to balance them if any of the cells were to fall below or above the protection circuit cut off levels. I even have a few single cell battery's for my cree flash lights and my hand held lazer that have built in protection circuits in the battery's and they bite the big one because if they ever for any reason fall below the cut off voltage or even if they ever go above it they stop working all together and no way to charge them at all and have to go in the trash. Some times if they ever go over you can just let them sit for a long time till the voltage drops low enough to let the cut off circuit open again and let power flow. but usually thats not the case tha they ever over charge and they instead go below the low cut off voltage and then can never be charged again. the non protected ones i have don't have that problem nore could they. Tho they could in theory be over charged if they were ever charged in a faulty charger. But the chargers I have don't put out enough volts to ever over charge them to the point they would ever explode any way. So the protected battery's are not as good as the non protected non smart ones.

 

[WessexWyvern]

To anyone who has had or is currently awaiting for their replacements, is DJI covering the cost of returning them to your dealer?

Regarding the small contact pads; seems to be plenty of pressure on mine, they were showing wear after relatively few flights. Not sure if that is a good or bad thing but the good plating has worn away in patches.
My concern is that the contact is not centralised or even. Any flexing in the chassis could easily break the contact momentarily. I'd be interested to know what the consequences of this would be?

This so called intelligent battery idea is hopeless, certainly the modular design idea. Something this critical should IMO have a positive plug in connection where there is little doubt over whether good contact is being made. I hope DJI are monitoring this thread and are taking note.