Solved lap top only charges 80%,its only 8 months old,windows 8

January 27, 2014 at 12:21:56
Specs: Windows 7
it used to charge 100%,but lately its stops at 80%,I thought the battery life would last a few years, can any body help,i would be so great full TONYX

See More: lap top only charges 80%,its only 8 months old,windows 8

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#1
January 27, 2014 at 12:45:34
✔ Best Answer
mmm... often seen this to be resolved by allowing the battery to discharge "fully" - totally flat etc... Then recharge...

I have seen suggestions/recommendations to allow a battery to fully discharge now and then - so as to prevent any memory effects (which lithium batteries are not "supposed" to suffer). Is said to prolong the life...

Some suggest remove the battery if running on mains power; as that too will lengthen battery life as battery will hold charge for a while and then it naturally decay...

I have an elderly/olde Acer Aspire (2005 at least) with the original battery still OK... It has been removed for periods of time - when it appeared to have charging problems; it wouldn't charge up properly. But after a total clean install/rebuild of the operating system (XP-Pro) the battery charges fine to a full 100%, and retains it too...

message edited by trvlr


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#2
January 27, 2014 at 12:48:45
Allowing the battery to fully discharge then charging it full is for calibrating the battery charging circuitry.

It does nothing for the actual battery cells, but calibrates the full discharge and charge state so the meter knows how to display the proper charge capacity.


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#3
January 27, 2014 at 13:09:01
mmm not quite sure I follow you there THX... But regardless, it won't hurt try it...

As I say that battery which wouldn't charge (in my olde Acer) does now - fully.

I picked up the idea etc.ages back - from assorted sites on the www, where it was promoted as wise and useful thing to do at intervals. And at one time Dell were advising not to leave the battery in-situ if running on mains power. Partly to reduce possible overheats (on some laptops) but also to extend battery life - by allowing it to discharge fully if not actually in use; and also occasionally running on battery to totally drain the cells... and then recharge as normal.


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Related Solutions

#4
January 27, 2014 at 15:03:50
"mmm not quite sure I follow you there THX"

There is actually a circuitry inside the Lithium Ion battery packs that keep track of how charged that battery is. In the old days of NiCad and Nickel Metal Hydryde, they would measure the battery state by voltage level but with today's lithium Ion batteries, the voltage is so steady right up to the point of the battery dying that they have to measure the charge state a different way. The circuitry measures how many coulombs flow out of the battery while being used and how many flow in while being charged. Occasionally this will need re-calibrating and that is what the purpose of draining the battery all the way down, then charging it fully.


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#5
January 27, 2014 at 15:10:11
Thank you kindly for that info; one learns something new everyday.

When Lithium cells arrived for hand held/portable tv cameras (as used in all broadcast environments today - and elsewhere too) we found it useful at intervals to drain them down fully; as otherwise after a reasonably lengthy period they would appear not to have much charge capability. I don't think many camera crews ever knew the how and why of it all...


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#6
January 27, 2014 at 20:12:18
In addition to all of the above information, if the charging cord is not putting out the proper voltage (low), the battery pack cannot reach full charge. If the deep cycle as indicated above does not fix things, try contacting the mfg. about possibly replacing the power cord/charger under warranty. Alternately, it should be marked as to the output voltage, if you test the voltage and it is actually low, then definitely look into a warranty replacement.

You have to be a little bit crazy to keep you from going insane.


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#7
January 28, 2014 at 08:49:45
Back in the 80's when I worked with camera men, they had to cart around 20 pound Ikegami cameras with huge lead acid batteries. I'm sure they welcome the new lighter Lithium Ion packs :)

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#8
January 28, 2014 at 09:14:59
Did you ever have to lug the Sony/JVC "portable" U-matic or similar VCR too… I had a few occasions where (as a cameraman - using a parrot/noddy-cam) I lugged an RCA TK76 (studio/portable) camera paired with one those "portable" VCRs… (One of my several roles in the mad world of broadcasting…) The weight of the VCR was appalling, and as one was tied to it via an umbilical - even if someone else lugged it for you… - it was by no means really mobile and easy to "run" (stagger) about… The camera weight was reasonably OK but the VCR was a joke… Ikegamis of course gradually became lighter - and batteries improved too… Nowadays the toys are so much lighter… almost too light, too small etc… And I have had a few chums who frequently took their slightly older kit on the road - as it was generally easier to use…; the lens assembly not being overly large compared to the camera body - compared to some of the newer models. But as it's all HD these days, and kwalitee has improved somewhat - there is a natural requirement to use the current/newer kit… And batteries can be more easily swapped out too… The U-matic were a pain to service too…, and tape jams (a not infrequent issue) were a frequent nuisance; a lot to be said for mini-discs and later SSD devices.

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#9
January 28, 2014 at 10:06:39
Even with the old lead acid cells it was unwise to discharge them until totally flat and could cause issues. What was described as "the fully discharged state" was not totally flat but to a quoted specific gravity.

Always pop back and let us know the outcome - thanks


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#10
January 28, 2014 at 10:19:30
That sort of rings a bell. My pa was a radio ham - pre and post war…; and I recall visits to the local "shop" to get freshly charged accumulators for the valve ccts. in his kit. And also at school all our wet cells were kept on a trickle charge programme - and regularly/daily checked (volts and specific gravity).

In some way many don't realise how much easier it is with batteries etc.. today...


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#11
January 28, 2014 at 11:15:51
Ah yes, the old Sony U-matic, I do remember those! I ran an audio production company way back when, luckily for me I didn't have much to do with the heavy video equipment but I would tag along with my buddy who did freelance video work. We mostly did work for TV commercials. We would have killed for the technology they have today!

Yeah, lead acid batteries were very picky and couldn't be drained too low or it would damage them.


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#12
January 28, 2014 at 12:14:28
Very crudely you could equate the "fully discharged state" as the "end of a batteries useful capacity". We used charge/discharge cycles on lead acid cells in strowger and crossbar telephone exchanges - happy days LOL.

Always pop back and let us know the outcome - thanks


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#13
January 28, 2014 at 12:53:55
Next we'll be back to Leclanche and Daniel cells - and if one digs a little further there were quite few others too…;-allegedly all the way to the ancient Egyptians, and ancient Greeks…

I remember after the war one could buy zinc-carbon battery kits; make your own zinc-carbon batteries…

And one can make a battery from (get volts out of) a lemon; get volts out of a tree; and also (so I have seem to have seen "somewhere") even a potato...


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#14
January 28, 2014 at 13:15:14
trvlr
Now you've got me - the ancient Egyptians were just before my time.

tonyx
Please excuse our "fun chat" - just pipe up and pull us back on topic.

Always pop back and let us know the outcome - thanks


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#15
January 28, 2014 at 14:07:56
On the subject of the laptop - my laptop (lenovo S205) came preloaded with software that could "prevent" the laptop from charging past a ceritan point (Lenovo Energy Management) that supposedly extended the life of the battery.

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#16
January 28, 2014 at 14:55:28
thank you all for the information,just learning about computers,i am letting my laptop run down at the moment,,once again thank you all ,will let you lot know how i get on,you lot sound like a good bunch of lads,,all the best TONYX

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#17
January 28, 2014 at 15:52:42
Yep, keep in touch - we'll try to stay on topic (no promises tho).

Always pop back and let us know the outcome - thanks


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#18
January 29, 2014 at 10:18:53
thomasad,

Yes, if you care for a Lithium Ion battery properly, you can really extend the life on them. Most cell phone manufactures push them to the very limits because a smaller battery means a smaller phone but also less run time. So they set the discharge limit to about 95-97% of fully drained on the battery and 95-97% full charge. This is why cell phone batteries will only last a year or so before you can notice degradation in the run time.

Now take Tesla Motors. They set the charge and discharge limits to around 80%. But by doing this they can get almost 8 years out of their Lithium Ion cells before noticeable degradation.


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