[solved]acer laptop leds blinking [del]Frequent static charge[/del]

Phalkon · 2015-12-20 12:49:03

Hi,

I have an acer laptop and I'm frequently removing the battery when I'm not using it as to keep it healthy for as long as possible.
However recently I started to encouter a small problem while putting the battery back in.
All the leds (the one on the power button and both of the ones on the side (indicating pc state (powered on, sleep mode) and battery state (charging, charged)) starts blinking.

It doesn't take much time to resolve this. All I have to do is turn off the pc, unplug the power source and pop out the battery, then hold the power button for few seconds for the static charge to discharge and then put everything back together.

At first I didn't worry about it much, but now it started happening quite frequently I just wonder if I'm doing something wrong.

When poping the battery out or putting it back in I usually keep the pc running. Never had any issues with that though and I think it shouldn't matter.

Any ideas why this might be happening?

Thanks for any replies.

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EDIT: RESOLVED

For anybody who might stumble upon this thread with the same problem, I had indetified what was wrong.
It was a bad AC/DC adapater. Either something was wrong with the adapter itself or with the cable or with the DC jack.
Motherboad didn't have had not enough current intensity to power the laptop and charge the battery at the same time.

Symtomps that indicate this problem:
All the leds blink when AC/DC adapter is connected as well as a battery. Also, when blinking laptop runs on battery (even though the adapter is connected).
When running without battery, laptop occassionally shuts down abruptly when doing high demanding tasks (eg. playing a game with discrete graphic card).
At these symptoms might be occuring only occassionally, but they'll will be more frequent over time.

Hope this would help somebody. There's scarce information on this issue on the web.

Last edited by Phalkon (2015-12-23 10:34:01)

mpan · 2015-12-20 15:53:02

I would expect that frequent removing and putting back the battery leads to damaging power circuit of a laptop pretty fast, and greatly increases chances of destroying other parts of the device due to transients. Possibly you're observing this. The solution seems simple:

Buy a new motherboard and replace.
Learn the lesson and stop doing pointless things in the future. I don't know where you have learned this, but removal of the battery makes completly no sense. It's a gibberish that may only have adverse effect on computer and even battery itself.

If you would have basic knowledge of electronics, I would suggest checking filter caps, voltage regulators and power transistors, and replacing them if needed. Might be cheaper than new mobo if you don't value your time high. But I assume that if you had it, this question would never appear .

Last edited by mpan (2015-12-20 15:55:59)

ewaller · 2015-12-20 16:42:29

mpan is right when it comes to modern batteries. These are not your father's Nickle Cadmium or Nickle Metal Hydride batteries. These are undoubtedly Lithium Ion or Lithium Polymer. These batteries have elaborate charging systems that properly handle charging process and are able to maximize the battery life through appropriate shallow discharge cycles, float, etc. It is harder on these batteries to allow them to self discharge off-line. The only reason I can fathom for removing them is if the computer has extended or frequent periods where the internal air temperature is way above room ambient.

mpan · 2015-12-20 18:18:20

Battery removal might make sense in any case (at any storage temperature) if the computer is not used for long time. Long time = weeks at least; and certainly if the time is counted in months. Not to prevent unneeded charge-discharge cycles, because one more will add nothing if compared to the number of the cycles in device's lifetime, but to avoid full discharge.

But only in such scenario. Avoiding charging to 100% if the device is not used on battery power immedietly after that is a much wiser solution to prolong its life. 80–90% is enough.

Phalkon · 2015-12-20 19:45:48

Thank you for the replies.

I'm certainly no expert on lion batteries, but this goes against anything I've read on them so far.

Lion batteries have a limited number of cycles in their lifetime and it's not good for them to leave them fully charged for extended periods of time.

As I use my laptop practically every day for at least 8 hours, it seems logical to try to avoid unnecessary cycles. But leaving the battery fully charged is not a good idea, therefore not using it at all seems as the way to go.

But if removing the battery is not a good idea, I have to be either wrong or I didn't realize some cons to removing the battery that outweigh the benefits.

EDIT:

mpan wrote:

I would expect that frequent removing and putting back the battery leads to damaging power circuit of a laptop pretty fast, and greatly increases chances of destroying other parts of the device due to transients. Possibly you're observing this. The solution seems simple:
Buy a new motherboard and replace.
Learn the lesson and stop doing pointless things in the future. I don't know where you have learned this, but removal of the battery makes completly no sense. It's a gibberish that may only have adverse effect on computer and even battery itself.

Well it is possible, but I doubt that replacing the motherboard is necessary. All I have to probably do is to stop removing the battery. As I said, these problems only occur when I'm putting the battery back in.

Also I should probably turn the pc down and unplug the powersource every time I'm handeling the battery, right? Would it remove the damages or at least minimalize them or does this have no effect on the matter?

Last edited by Phalkon (2015-12-20 19:59:01)

ewaller · 2015-12-20 21:29:00

They do have a limited number of cycles, measured in the 100's. And you are right, long term storage is better at lower states of charge. 40% seems to be optimal. But, to go from full down to 40% and back up to full constitutes 60% of a cycle. You only get a couple hundred full cycles. On the other hand, permanent loss of storage will occur at a few percent per year at 40% SOC and at several (perhaps 10%) at 100% SOC. So... Do you kill the battery by subjecting it to unneeded cycles to take it down to 40% every time you put it into temporary short term storage, or is it better just to leave it charged and suffer the slightly higher rate of death at full charge? If I were to take the batteries out of service for a year, yeah, run it down to 40% first, then store it in a nice cool place (15C). If you did it weekly, you would kill the battery much faster than if you just left it in place. Monthly? It might be the cross over point.

I leave my batteries in and run on AC most of the time. When the power fails, the batteries keep my system alive. Batteries in my laptops tend to last about 3 years. It costs about US$120 the last time I had to buy a battery. Unlike laptops from some fruity companies, it sounds like your batteries are easily replaceable.

Here is a pretty good article http://batteryuniversity.com/learn/arti … _batteries

ESD, if that is what is causing the upset, will destroy things whether or not they are powered. Maybe this is another reason to just leave them in place. Batteries are usually hot swapable, so powering down is probably just preventing the upset.

Edit: BTW, this battery has been in service since April and is showing no signs of deterioration. This house was kept at about 27C in the summer and this laptop runs 24/7

ewaller@turing /sys/class/power_supply/BAT0 1033 %cat charge_full
3040000
ewaller@turing /sys/class/power_supply/BAT0 1034 %cat charge_full_design 
3040000
ewaller@turing /sys/class/power_supply/BAT0 1035 %cat charge_now        
3040000
ewaller@turing /sys/class/power_supply/BAT0 1036 %

Last edited by ewaller (2015-12-20 21:33:40)

Phalkon · 2015-12-20 22:21:24

ewaller wrote:

Edit: BTW, this battery has been in service since April and is showing no signs of deterioration. This house was kept at about 27C in the summer and this laptop runs 24/7
ewaller@turing /sys/class/power_supply/BAT0 1033 %cat charge_full
3040000
ewaller@turing /sys/class/power_supply/BAT0 1034 %cat charge_full_design 
3040000
ewaller@turing /sys/class/power_supply/BAT0 1035 %cat charge_now        
3040000
ewaller@turing /sys/class/power_supply/BAT0 1036 %

Impressive. Mine is already at 69% of the full design charge, although it is about 3.5 years old, so I guess it's still quite good. And I do use the battery quite often actually, it gets to rest only on weekends and in the evenings so I guess there's really no point in taking it out.

ewaller wrote:

On the other hand, permanent loss of storage will occur at a few percent per year at 40% SOC and at several (perhaps 10%) at 100% SOC

Interesting, so the difference is say 4% - 10% percent? Maybe slighly bigger?
Well I expecteded much bigger difference to be honest. Here I am, thinking how much smarter I'm for taking the battery out when it probably didn't do me much good anyway.

Although maybe it did. I have optimus with intel and nvidia graphic cards. And running games with nvidia tends to build up heat pretty quickly, especially in the summer. I suppose that is a good reason to take the battery out even if it is for a short period of time, isn't it?

ewaller wrote:

ESD, if that is what is causing the upset, will destroy things whether or not they are powered. Maybe this is another reason to just leave them in place. Batteries are usually hot swapable, so powering down is probably just preventing the upset.

Wait, I don't understand. Are you saying, that powering down only prevents the leds from blinking? Well this upset won't disappear when rebooting. You have to really take the battery out, unplugg the power source and hold the power button for a few sec to discharge.
I think there is some kind of safety feature, that prevents the ESD from doing any damage. It should work even when powered down. The leds would simply start blinking when the pc is powered on and you would have to discharge the build up static charge anyway.
But that's just what I think. I don't really know how this works and didn't find anything on it except how to discharge it.

ewaller · 2015-12-20 23:13:41

ESD events can do strange things. When one talks about susceptibility of electronics systems, there are two things we consider. Burn out and upset. Burn out is permanent damage to a device caused by an electromagnetic event. It turns out that an ESD can damage a semiconductor device without killing it completely. But damage is done and is progressive Some examples here. The other thing is upset. Upset is when the event puts the device into an unknown or illegal state. Sometimes this can be cleared by itself, as in a well designed state machine that detects illegal states and forces itself back to a known state after detecting an illegal state. Sometime they can be cleared by a reset of the device, as in a state machine that is not well designed and wanders around from illegal state to illegal state. Other times you must remove power as in the case of latch up. Both damage and upset can occur in response to a single event.

Note that it is entirely possible that the system is just being stupid and entering an illegal or protective state based upon a communication error with the battery -- in fact that is likely. But, the thread title does talk about static

By the way, arguing over battery hygiene is one of those topics that electrical engineers will argue over ad nauseum. So is ESD protection You stepped in both. At least we did not invoke thermodynamics and cooling.

Last edited by ewaller (2015-12-20 23:14:19)

Phalkon · 2015-12-22 13:58:47

UPDATE: The upsets started to happen even without the manipulation with the battery.

The upset appears only when the battery is in and the cable plugged in. It disappers when I unplug the cable, but then reappers when I plug the cable back in. Also, even when plugged in the system runs on battery power (I think this is a safety feature of the laptop).

Personally, I think the battery is dying. Can upsets be caused by a bad battery? Is it likely that this is the case?

EDIT:

ewaller wrote:

Note that it is entirely possible that the system is just being stupid and entering an illegal or protective state based upon a communication error with the battery -- in fact that is likely. But, the thread title does talk about static

That would make sense. Could this error be indication of a bad battery?
The charge of the battery is dropping faster and faster. I think this is quite normal given the battery is 3,5 years old, but with the communication errors, I think the end of its days is near.

Last edited by Phalkon (2015-12-22 20:56:11)

Phalkon · 2015-12-23 10:26:13

For anybody who might stumble upon this thread with the same problem, I had indetified what was wrong.
It was a bad AC/DC adapater. Either something was wrong with the adapter itself or with the cable or with the DC jack.
Motherboad didn't have had not enough current intensity to power the laptop and charge the battery at the same time.

Symtomps that indicate this problem:
All the leds blink when AC/DC adapter is connected as well as a battery. Also, when blinking laptop runs on battery (even though the adapter is connected).
When running without battery, laptop occassionally shuts down abruptly when doing high demanding tasks (eg. playing a game with discrete graphic card).
At these symptoms might be occuring only occassionally, but they'll will be more frequent over time.

Hope this would help somebody. There's scarce information on this issue on the web.

Lone_Wolf · 2015-12-23 14:57:09

Hmm,off-topic board is blocked for search engines.

Maybe ask mods to move this thread to Kernel & Hardware board ?

ewaller · 2015-12-23 15:09:50

Moving to Laptop Issues. I missed that this was in off-topic

Arch Linux

#1 2015-12-20 12:49:03

[solved]acer laptop leds blinking [del]Frequent static charge[/del]

#2 2015-12-20 15:53:02

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#3 2015-12-20 16:42:29

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#4 2015-12-20 18:18:20

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#5 2015-12-20 19:45:48

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#6 2015-12-20 21:29:00

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#7 2015-12-20 22:21:24

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#8 2015-12-20 23:13:41

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#9 2015-12-22 13:58:47

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#10 2015-12-23 10:26:13

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#11 2015-12-23 14:57:09

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

#12 2015-12-23 15:09:50

Re: [solved]acer laptop leds blinking [del]Frequent static charge[/del]

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