Orpington Astronomical Society

Astronomy => Technical => Topic started by: ApophisAstros on Mar 13, 2019, 16:59:07

Title: Laptop Battery
Post by: ApophisAstros on Mar 13, 2019, 16:59:07
On my Laptop if i unplugged the charging cable it switched off almost straight away and so took advice and was told that if the cable was plugged in all the time it can stop the battery from taking a charge. So i swapped the battery from my 2nd Laptop and now when the battery is fully charged i unplugged the cable and each time have got longer and longer until one charge lasts for 5.5 hrs.
Just wondered if anyone had similar experience or advice?
Roger
Title: Re: Laptop Battery
Post by: The Thing on Mar 13, 2019, 17:08:45
The battery had a chip which learns charge levels. They need reeducating occasionally.

Fyi. I just revived a power tool battery by zapping it with an old car battery charger for 5 mins. The smarty pants charger thought the battery (14.4v) was knackered as it had zero detectable charge after not being used for a few months.
Title: Re: Laptop Battery
Post by: Carole on Mar 13, 2019, 19:04:52
I must admit I do tend to plug it in most of the time, but mine last quite a while on battery before they go flat.  I try to make a point now and then of just using the battery.

Considering my laptops are a darn site older than yours Roger, I find yours switching off almost immediately quite surprising.

Carole
Title: Re: Laptop Battery
Post by: ApophisAstros on Mar 13, 2019, 22:17:22
i think i never unplugged it though and these new lithium batteries need to discharged and be recharged regularly,
Roger
Title: Re: Laptop Battery
Post by: RobertM on Mar 14, 2019, 00:14:03
Quote from: Apophis on Mar 13, 2019, 22:17:22
i think i never unplugged it though and these new lithium batteries need to discharged and be recharged regularly,
Roger
Nearly all rechargables do.  I always try to run rechargables right down each time but it's more difficult with laptops as we tend to use them plugged in :roll:

Robert
Title: Re: Laptop Battery
Post by: NoelC on Mar 14, 2019, 10:28:56
I think there are several different technologies.  Bought a new battery for my laptop (which lasted for ages when it was new) instructions with it explicitly state;if you keep it plugged in, you will damage the battery and it won't hold charge.  It definitely benefits from being cycled, however, my wife's apple requires the battery to be plugged in wherever possible.

Suspect there is a chip in more advanced ones that control the charge curve, whereas the older (more basic) batteries like mine require regular cycling to avoid discharge memory effect.
https://www.wikihow.com/Revive-a-Dead-Laptop-Battery (https://www.wikihow.com/Revive-a-Dead-Laptop-Battery) (not tried sticking mine in the freezer!)
https://phys.org/news/2013-04-memory-effect-lithium-ion-batteries.html (https://phys.org/news/2013-04-memory-effect-lithium-ion-batteries.html) (just states what we all know, but gives the physics of it.)
Noel
Title: Re: Laptop Battery
Post by: The Thing on Mar 15, 2019, 10:18:56
My Tosh Satellite laptop lives in the observatory and its always plugged in and booted up. The battery lasts a few hours if needed, the laptop was purchased Wed, 24 Apr 2013. So it's nearly 6 years old and has survived many deep sky camps. It was a refurbished model. My previous Tosh needed regular full discharge/recharge cycles to keep the battery in condition.
Title: Re: Laptop Battery
Post by: ApophisAstros on Mar 15, 2019, 10:24:35
Is that an ION battery Duncan as that's what it says on mine,
Roger
Title: Re: Laptop Battery
Post by: Mac on Mar 15, 2019, 20:47:52
I had the same issue with a dell laptop,
The work around (as per dell) was to do the following,
Boot the laptop in to bios normally F2.
you may or may not have a battery tab,
If you go to the battery tab the might be a reset butt which you can select.
All this does is reset the battery level to flat and then lets the battery completely discharge to zero whilst booted in the bios screen.

If you dont have a reset on that tab or you might not even have a battery tab, but boot to the bios, and leave the laptop to run the battery completely down,
Once it shuts off, reboot into bios and repeat untill the laptop fails to boot in to the bios. It might take a couple of reboots, but the second reboots shouldn't take long,

Then plug the charger in and boot the laptop.

Windows will eventually boot and the battery will report to it that its 0% ish and you can then watch it charge up to full.

If after that it still dies when you remove the battery, chances are the battery is cooked.

Mac.