Ticket #6092 (closed defect: fixed)

Opened 7 years ago

Last modified 6 years ago

Battery Charging problems. (Collector bug)

Reported by: rsmith Owned by: rsmith
Priority: high Milestone:
Component: embedded controller Version:
Keywords: Cc:
Action Needed: never set Verified: no
Deployments affected: Blocked By:
Blocking:

Description

There are various "battery won't charge" problems. I received some RMA units with these problems this week. Cause is under investigation

Attachments

BATTERY.DMP (128 bytes) - added by frankprindle 7 years ago.
battery.dmp file
log-FCP-080202-222854.csv (4.8 kB) - added by frankprindle 7 years ago.
olpc-logbat file
log-vandien-080314-062328.csv (0.8 kB) - added by vandien 7 years ago.
battery.dmp-vandien (128 bytes) - added by vandien 7 years ago.

Change History

  Changed 7 years ago by frankprindle

Richard, I returned my original XO due to sticky key problems. Received my replacement on Tuesday 1/29/08. No sticky key problems so far, but the bad news is that the battery simply won't charge. The first time I tried unplugging the power supply, the XO ran for about 10 minutes and then just shut down without warning. Now no amount of charging gives me any operation time with the battery. When the supply is plugged in, the battery indicator is solid green indicating fully charged, and the sugar battery meter is filled and reads "Battery fully charged". Nonetheless, removing the power supply causes immediate shutdown, and it won't boot at all until I reinstall the power plug. The unit came with Q2D06/650. I updated to Q2D07/656, but still have the same behavior. Does this mean I need to return the whole unit again, or just the battery?

This is not fun.

follow-up: ↓ 3   Changed 7 years ago by frankprindle

Update - after 8 hours (overnight) charging, my XO was able to both boot and run on battery power for a grand total of 4 minutes. During that entire time, the sugar battery meter showed a 99% charge. The next time I pushed the power button, it stayed on for about 5 seconds. The next time, nada. What do you make of this? :*(

in reply to: ↑ 2   Changed 7 years ago by rsmith

Replying to frankprindle:

Update - after 8 hours (overnight) charging, my XO was able to both boot and run on battery power for a grand total of 4 minutes. During that entire time, the sugar battery meter showed a 99% charge. The next time I pushed the power button, it stayed on for about 5 seconds. The next time, nada. What do you make of this? :*(

Please follow the instructions posted here:

http://lists.laptop.org/pipermail/community-support/2008-January/001320.html

And then attach the data to the ticket. (or mail it to me). If you can't find a usb keyboard then we can modify the instructions a bit but we can make them work

Changed 7 years ago by frankprindle

battery.dmp file

Changed 7 years ago by frankprindle

olpc-logbat file

follow-up: ↓ 5   Changed 7 years ago by frankprindle

Here you go, Dr. Smith... I anxiously await your diagnosis. It would be really great if I can get this puppy up before next Thursday!

By the way, your procedure resulted in the laptop running on battery for only around 8 minutes before shutting down. Nearly as long as the first time I removed power, but clearly the procedure itself didn't fix the problem.

in reply to: ↑ 4   Changed 7 years ago by rsmith

Replying to frankprindle:

Here you go, Dr. Smith... I anxiously await your diagnosis. It would be really great if I can get this puppy up before next Thursday!

First: Upgrade your firmware. You are running Q2D05 which is a brick waiting to happen. If your RTC gets an invalid date in it your machine will quit booting and the only way to recover it is to re-flash the SPI flash with special tools. Upgrade to D07 (stable) or D11 (proposed Update.1 candidate). Details on the wiki.

By the way, your procedure resulted in the laptop running on battery for only around 8 minutes before shutting down. Nearly as long as the first time I removed power, but clearly the procedure itself didn't fix the problem.

It wasn't supposed to fix anything. Its just so I can see whats going on. All that did was clear the % capacity so that the EC thinks the battery is at to 0% and it to try to charge. Otherwise the EC has it marked as full and won't try and charge.

diagnosis:

1202009368, 1202009378,75,6469660,1227213,2016,864,Charging,Normal 1202009388,75,6570920,1392057,2044,874,Charging,Normal

On insertion of the battery this looks ok

... 1202009682,78,7127850,1262109,2418,1131,Charging,Normal 1202009692,78,7526180,260,2425,1136,Charging,Normal

About 5 minutes later the voltage on the battery crosses the CC to CV threshold and your charging current drops from 1.2A to essentially zero (260uA which is measurement noise). This is the abnormality. It should have taken much longer to get to 7.1V

Right now this fits the mold of many of the other charging problem reports. I don't yet know whats up but I suspect that the battery has a problem. I don't yet have all the battery RMAs so I can't make any grand claims yet.

batman.fth has the ability to manually charge your battery. Lets force some charge down the batteries throat and see what happens.

load up batman.fth and do:

1w-init bat-charge <enter>

Now the EC is in reset and you have forced the charge circuit on. The only way its going to be turned off is to remove all power from the XO or hit a key on an attached USB keybaord. So please do not leave the unit unattended. And please don't leave it on for an extended period. If you grossly overcharge the battery it will damage the battery. If your battery is funky then I need it in that state so I can work with the mfg to figure out whats up.

Values printed to the screen are the ACR, Voltage, Current, and delta ACR. There is no logging yet. Thats my next feature.

Watch the voltage and current readings and see what they do. Watch the current to see if it follows what happend in the olpc-logbat data where it suddenly dropped. Also watch the delta ACR. The batteries are about 3000mAh batteries so since you are very low you should be able to put 2500mAh in them without any problem. Note that delta ACR is reset every time you run so keep track of the total ACR delta if you stop and re-start the charge.

I'm currently not tracking battery temperature either (also next on the list) so periodically hold the XO with our palm on the battery and see if it gets really hot. While charging it will get hot but make sure its not really hot.

So start small and see if the battery continues to take charge after your 5 minute mark. If so then continue on up to .5 hour.

If the battery actually takes a charge then put it back in the XO run olpc-logbat. Note that using batman.fth to charge will confuse the ECs understanding of the charge state but it will eventually sync back up. The % capacity number reported may be totally wrong.

Then see what the EC does when you try to charge it normally (with olpc-logbat going).

If it works then repeat the process with about 1h charge time, noting how much delta ACR was added. Then run it on the XO with olpc-logbat going and then try to recharge normally (with olpc-logbat going)

Then lets look at all your data again.

Sorry the above is somewhat vague but this is new territory.

follow-up: ↓ 8   Changed 7 years ago by frankprindle

Richard, I will try what you ask and post what I find out here.

One thing though - I AM running Q2D07 firmware - I know this for 2 reasons: 1) I flashed the XO with the latest release, which is 656+Q2D07 and it did go through the process of reflashing the OFW; and 2) cat /ofw/openprom/model reports Q2D07. I have no clue why olpc-logbat lists a different firmware in the log; perhaps you do.

follow-up: ↓ 9   Changed 7 years ago by frankprindle

Richard, I couldn't run "1w-init bat-charge" from the USB keyboard because it would just run one cycle and then came back with 2 "ok" prompts (no clue on why). So I unplugged the USB keyboard and repeated this using just the XO keyboard, realizing that I could only stop it by pulling the power and the battery.

The results were pretty discouraging. It charged at 1.2A for about 2 minutes or less. When the voltage reached 7.1V, the next line said 7.5V and the charging had stopped (0 ma.) So the total capacity of the battery seems to be around 40 mah. Not a very useful battery, I would say. After pulling the power and battery, attempting to run with just the battery worked initially but the battery indicator was red and it shut down after about 6 minutes. I guess that's what you get out of 40 mah.

Is there a way I can RMA just the battery? So far no sign on this XO of the sticky keyboard problem (oddly, as weighed by fedex, this also weighs a pound more than the unit I returned, and it feels a little heftier too!!!) and I would hate to send the whole thing back and get a second replacement with a good battery and another bad keyboard (I've seen reports on the olpcnews forum of this happening).

Or maybe you could send me a known good battery, I could swap it in, and if it behaves normally, I can send you back the rogue battery; if it still misbehaves I can send you back the good battery and RMA the whole XO as a total charging system problem.

in reply to: ↑ 6   Changed 7 years ago by rsmith

Replying to frankprindle:

Richard, I will try what you ask and post what I find out here.

and 2) cat /ofw/openprom/model reports Q2D07. I have no clue why olpc-logbat lists a different firmware in the log; perhaps you do.

Ok. Yeah. I do.. I forgot that log bat lists the EC version code listed and not the overall version. It can be confusing when they differ. Which happens when OFW changes but the EC code does not. I should list both in the log.

in reply to: ↑ 7   Changed 7 years ago by rsmith

Replying to frankprindle:

Richard, I couldn't run "1w-init bat-charge" from the USB keyboard because it would just run one cycle and then came back with 2 "ok" prompts (no clue on why).

Oh yeah. I've hit that as well. Thanks for reminding me. I need to make my test case and file a bug. Seems to be an issue with OFW and usb keyboards. It sometimes thinks a key is pressed. If you do it enough times it eventually runs.

The results were pretty discouraging. It charged at 1.2A for about 2 minutes or less. When the voltage reached 7.1V, the next line said 7.5V and the charging had stopped (0 ma.) So the total capacity of the battery seems to be around 40 mah. Not a very useful battery,

Ok. Thats almost exactly like the other unit I have. What I think is happening is that there is a poor connection somewhere in the battery and after a few minutes of charging it heats up and goes high resistance..

Is there a way I can RMA just the battery? So far no sign on this XO of the sticky keyboard problem (oddly, as weighed by fedex, this also weighs a pound more than the unit I returned, and it feels a little heftier too!!!)

Its heavier? Thats odd. There's no official way to RMA just the battery. I'd like to get your battery though. Let me discuss with others on Monday and see if I can work something out.

and I would hate to send the whole thing back and get a second replacement with a good battery and another bad keyboard (I've seen reports on the olpcnews forum of this happening). Or maybe you could send me a known good battery, I could swap it in, and if it behaves normally, I can send you back the rogue battery; if it still misbehaves I can send you back the good battery and RMA the whole XO as a total charging system problem.

Changed 7 years ago by vandien

Changed 7 years ago by vandien

follow-up: ↓ 11   Changed 7 years ago by vandien

Hey Richard, I'm responding to ticket #5652

My battery doesn't hold a charge at all now. Followed the instructions you posted above and the laptop dies as soon as I pull the plug. I'm attaching the olpc-logbat and battery.dmp anyways.

I'd like to replace the battery as I gather that seems to be the problem. Is there a way to do this without RMA'ing the entire unit?

Thanks for your hard work!

in reply to: ↑ 10   Changed 7 years ago by rsmith

Replying to vandien:

I'd like to replace the battery as I gather that seems to be the problem. Is there a way to do this without RMA'ing the entire unit?

Nope. Right now its all or nothing Have you opened a support request by sending mail to help@… with your problem? If not then please do so.

  Changed 6 years ago by rsmith

  • next_action set to never set

There is a new possibility for people with charging problems.

Please see:

http://wiki.laptop.org/go/XO_LiFePO4_Recovery_Procedure

  Changed 6 years ago by gregorio

  • milestone deleted

Milestone Never Assigned deleted

  Changed 6 years ago by rsmith

  • status changed from new to closed
  • resolution set to fixed

Solutions for battery problems are on the wiki.

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