What would you do? (lipo laptop charging situation)
xanadu
Posts: 3,347
I've got this weird situation on my hands and don't know what to do. All names are fictional.
Background Info:
Acme sells us 50 laptops every four years, the laptops are great. Their care program for accidental damage is about two week turn around time for a totaled laptop. The laptops cost around $2800 each. We have some people that use them plugged into AC all day, and some mobile people that use an external dual battery charger. They swap packs 2-3 times a day.
The Issue:
About six months ago the external dual chargers started charging the batteries for an hour or so then tripping some fail safe. Blinking red status LED, and charging stops. It seems to be random and not have anything to do with the dual battery chargers AC input side.
Importantly, the laptops have no issues charging the batteries, only the external dual pack chargers have a problem. Because of all that and swapping AC power supplies, I assumed it was the chargers and they were not under warranty. I am really good at troubleshooting issues like this. Acme's tech support said they never heard of anything like it before.
I ordered a couple new batteries to test out, and they do the same thing. So the boss takes it upon herself to order 15 new dual chargers at $80 ($1200) which includes the AC supply as well.
New chargers, same deal. So I call Acme tech support and they say well it must be the batteries so and she orders 50 new batteries at $120 ($6000)!
We ended up keeping it all just to get through the day. Fast forward a couple months.
I come to the determination that the people who use the laptops are not gentle with plugging in the batteries. It's not a drop in style charger, you plug the connector in and kind of snap it off. I noticed a lot of the plastic around the connector on the battery is broken. So I think the external chargers may notice this while the charger built into the laptop does not. The only other variable is the AC side, and again there is no way that is it.
So basically it comes down to people being to rough. Acme would have to know about it if we had all bad stuff so would other people. That is the only thing I can think of.
My Question:
Do you think it would be wise to override a laptop battery charger fail safe by continually "rebooting" the AC side? Doing this seems to work fine and the batteries will eventually charge if you reboot the charger about once an hour. They also wouldn't be out $7200. Whatever is causing the charger to fault cannot be determined, but it isn't hot or anything. It could also only happen when people are there and not overnight. I am at a total loss what do you think?
Background Info:
Acme sells us 50 laptops every four years, the laptops are great. Their care program for accidental damage is about two week turn around time for a totaled laptop. The laptops cost around $2800 each. We have some people that use them plugged into AC all day, and some mobile people that use an external dual battery charger. They swap packs 2-3 times a day.
The Issue:
About six months ago the external dual chargers started charging the batteries for an hour or so then tripping some fail safe. Blinking red status LED, and charging stops. It seems to be random and not have anything to do with the dual battery chargers AC input side.
Importantly, the laptops have no issues charging the batteries, only the external dual pack chargers have a problem. Because of all that and swapping AC power supplies, I assumed it was the chargers and they were not under warranty. I am really good at troubleshooting issues like this. Acme's tech support said they never heard of anything like it before.
I ordered a couple new batteries to test out, and they do the same thing. So the boss takes it upon herself to order 15 new dual chargers at $80 ($1200) which includes the AC supply as well.
New chargers, same deal. So I call Acme tech support and they say well it must be the batteries so and she orders 50 new batteries at $120 ($6000)!
We ended up keeping it all just to get through the day. Fast forward a couple months.
I come to the determination that the people who use the laptops are not gentle with plugging in the batteries. It's not a drop in style charger, you plug the connector in and kind of snap it off. I noticed a lot of the plastic around the connector on the battery is broken. So I think the external chargers may notice this while the charger built into the laptop does not. The only other variable is the AC side, and again there is no way that is it.
So basically it comes down to people being to rough. Acme would have to know about it if we had all bad stuff so would other people. That is the only thing I can think of.
My Question:
Do you think it would be wise to override a laptop battery charger fail safe by continually "rebooting" the AC side? Doing this seems to work fine and the batteries will eventually charge if you reboot the charger about once an hour. They also wouldn't be out $7200. Whatever is causing the charger to fault cannot be determined, but it isn't hot or anything. It could also only happen when people are there and not overnight. I am at a total loss what do you think?
Comments
To be honest, my first thought was to suggest what I did when I needed to get over 8 hours of run time for my laptop. Since I already had an 18V cordless drill with 2 batteries and a charger I scrounged up a bad charger to get the contacts for the battery, soldered a cord with barrel connector to the contacts, and ran on one battery while the other was charging. Worked like a charm, although it might not be too practical in your case.
But it really comes down to several components that have to be right.
a. An outboard charger that also works as an alternative a/c mains power source even if the battery is not present.
b. A lithium cell battery pack which includes thermal sensing and state of charge sensing to optimize use of the battery, and to maybe acquire and report history performance of the battery pack.
c. A portion of the laptop's BIOS is specifically written to address lithium cell power. It monitors heat, state of charge, presence of the the charge, choices for power conservation, fan operation, and more.
So it is not a simple system to fool around with. Some brands can accept a simple generic replacement for a power supply; while others actually verify that the power supply is their brand and will accept no other... even with appropriate voltage and current.
Historically, there have been periods where manufacturer's got the designs wrong and either a lot of chargers were defective or a lot of battery packs were defective. My early EEEpc had a wall wart that was prone to failure. Early Compac laptops seemed to have had a lot of bad battery packs.
With my EEEpc, the failure of the wall wart was slow and since I had installed Ubuntu Linux, I was getting a lot of messages from Ubuntu that made no sense. A huge amount of discussion on the internet was then created about fixing the Ubuntu software bug in its battery management software. In other words, perceptions can get really distorted as to where and what is the nature of the failure. One flies off into loading other distributions of Linux, buy a new battery pack, and only in the end finding that it was the wall wart that was the offending device.
It is often just simpler to take the laptop into a manufacturer's service center and have them deal with the problem. If they get it wrong, you can demand they take back the parts they sold you unnecessarily. If you are trying to do it on your own, you may throw a lot of money in several directions that shouldn't have been pursued.
That is pretty cool actually cordless drill batteries are rugged and would make good packs for all kinds of stuff I bet.
The only Propeller project I saw here was to mount a relay in places of the AC switch on a power strip and have a RTC+Prop timer scheduler. Then I thought it should probably be CE and UL listed etc etc and found a nice programmable timer online. Plus I'm still trying to figure out this log table stuff...
I'm not going to install a timer, it's not even my problem anymore. I was little upset someone spent $7200 I guess lol.. They're going to have to live with it as it is, and I will push to get more authority over purchasing.
If I get that right, would it be possible to use the laptop running off of an inverter in the field when possible and unplug as you need to leave that source?
Lipo batteries are really sensitive and one bad cell can tell a charger to kick off. I don't know these kinds of systems well, but others I use have a system that continously balance the cells within the pack. If one cell goes bad the pack will fail.
Do the new batteries work with the old chargers?
If so, you might try a thick rubber band to insure a connection, and or understand what a connector sensor, if present, is looking for.
That's right the laptops charge the batteries fine. The external dual pack charger after about an hour will stop charging them. The mobile users don't need to charge in the field. They aren't out long enough to need to, there is a battery station where everyone swaps out packs.
Two different buildings/charge stations, 150 batteries, 30+ chargers, 50 laptops, none of it is working properly except plugging the laptop into AC.
The new and old batteries and chargers match and are compatible. There are two brands of batteries both doing the same thing as well. Some of the plastic is broken on most of the batteries and at this point that is all there is to go on. It's not bad enough to cause a short though a lose connection might be possible.
Here is a not broken one:
This is the DC side of the external charger.
A red flashing light means it is charging a pack below 20%, it's the status indicator not the charging indicator that is blinking red though. There isn't anything in the manual about red flashing light only solid, and Acme tech support says, "it must be the batteries."
Above I mentioned the status LEDs blink red, when in fact they stay on solid, long day.
This one isn't in too bad of shape, some are worse. Not all are broken. So, if it has something to do with broken batteries, they would have to be "breaking" the chargers to not work with the non-broken batteries as well.
Here is the external charger plugged into a battery.
Here's a video of what happens.
[video=youtube_share;Rv7cePnLtEs]
So something about the external charger doesn't like these batteries, when they charge just fine in the laptop. Across the board....
I mentioned it, because we had a similar issue with a charger and a couple of batteries, and it turned out the laptop case, with it's battery snaps and such, insured a great connection where the charger didn't always get one. In that case, it was both a crappy connection, and a connector sensor / switch not being engaged, forcing a low energy charge, safe state. Never would fill the battery. Worn / broken plastic would fail to trigger the "yeah, it's connected" switch.
Yours have more engagement between the terminals, which seems favorable. Not likely to be mechanical, particularly given the batteries across the board fail. Annoying as all get out, particularly as I don't see a sensor / switch on your setup. It's just crappy gear.
Well, thanks for the picture!
Perceptions of damage and throwing money at the problem in a wholesale fashion lead to the premature replacement of a lot of digital electronics.
I have an ASUS wifi router loaded with custom Linux firmware. It suddenly started to act strange and I was about to start over with a new router. But some investigation indicated that router wallwarts are the 'sacrafical lamb' when you get local lightning strikes on your AC mains. So I just replace the wall wart with a better one and all is well.
The trick to establish an intelligent and thorough means of investigation if you are going to manage your money wisely in repair or replacement situations. There is a whole wasteful culture out there that just won't do this and buys a complete new unit.