Lithium battery laptop revive

[robint]

Hi All
I hope this is in the right category
I just want to give something back here ( as EEVblog has really helped me) with my recent success reviving a laptop (Acer Aspire One) Netbook.  A trusty 20 years old little friend still going strong on Win XP rev 3 and indispensable from the days when you had control over your life.
I hadnt used it for perhaps a year or more and powered it up and saw that the battery pack wasnt charging.  I saw it was difficult to source a replacement cos the form factor was one of many different shapes and sizes.
That was when makers deliberately made 100's of different forms so you would have to probably buy a new laptop when your lion batteries wore out (they even put count down chips to disable your pack after ca 600 cycles - just like ink cartridges had - till EU outlawed the practice cos of the mountain of industrial waste this practice produced - same applies to laptop.  If you do your YT homework its surprising easy to repair a lion battery pack. YMMV

So I did and at no cost, revived a pack that had discharged  below the lock out level ca 2.5v  imposed by the BMS cct.
I prised open the casing and found 2 oo 6 cells down to 1.9v.  All the BS on the web will tell you to send them to a recycle depot    Rubbish

I followed the advice to charge the two cells at 1mA directly across the cells.  The ocV came up to 2.5v, then I up the charge to 30mA to ocV 3.2V as per the other 4 cells deemed ok.  Reassembled the pack roughly and put it back into the laptop and plugged in the psu block.  Started up Win and the battery app said 20% remaining but was charging.  2hrs later, I had full charge 100%.  So I shut down/restart and removed the psu and left it running 30 mins.  I have my m/c set to power save so the screen powered off after 5 mins.  but on refresh I had only used ca 5% of available capacity.  WHAT A RESULT
I should say that I rarely used my m/c on battery and only expected the battery to perform as a UPS, so generally very little deep cycle use (good for battery life).

So that saved me £30 for some dodgy? alt replacement pack.

I herewith post some links to YT vids and others that may help someone else with an old cherished laptop.

https://www.nature.com/articles/srep30248


I strongly recommend bigclivedotcom as a source of genuine info (not the usual waste of time BS vids and comments by armchair puff adders and worse infomercials pushing their brand and expensive products etc.

https://www.youtube.com/@bigclivedotcom/search?query=lithium%20batteries 

BCDC has been going over 10 years and has ca 700vids of personal experience and workbench tear downs - amazing wealth of knowledge packed in his site - and he is not sponsored or selling anything

I daresay many EEVblog members will already know of this invaluable source of (sometimes weird) topics - well he does live on the IoM

Hope this helps
Robin