Lenovo T14 Gen1 no power with a new battery after the original battery failed

[mon2]

Can you link the schematic? Do not post it here but only link it once they are in the schematic forum.

The capacitor voltage is important and 25v is safe for this area. Post a screen grab of the schematic for these parts if available to you.

[keepread]

If I had schematics, I would not have been asking questions here

[mon2]

..

[keepread]

Highlighted in yellow, as I presume?
Thanks a million!

[mon2]

Yes. Found these values using a similar model from Lenovo T14. The physical 0603 size should be ok for your board since many of the other parts are a match. If you are ordering from Digikey or Mouser - consider to also order the 0805 sized parts of the same value. They will be very inexpensive. DK is +$8 for shipping to Canada with next business day delivery.

[keepread]

mon2,

Do you happen to have the schematics for the power bus of another Lenovo? This time it is IdeaPad S400 and here are all of the numbers I can see on it.
One after another, two replacement batteries got shipped to me, and they both fail but differently.
The first one quickly charged to 100% but then only held for 15 min and said that its capacity became 12% of design capacity.
The second one says that it charges but always shows 80% charge and does not hold at all.
I'd like to eliminate the possibility that it is the laptop's fault before I go blame the battery seller.

[mon2]

I do have the schematic for this model. The logic board is part # LA-8952PR01.

[keepread]

Mon2 has a heart as big as a whale! Thank you so much for this!

It is too early to feel confident and call it a day, but it looks like the reason for the 2nd replacement battery to have issues was contaminated contact blades. I ended up removing and reinserting it a dozen times, and it began to take and hold charge. They have probably been stored in a humid environment for so many years and got oxidized. The 1st one is still dead though.

[mon2]

Np. You can try some of the ideas here:

https://www.reddit.com/r/batteries/c...ery_corrosion/

Ironically, last night had to replace some dead 'AAA' from a Costco heater remote which was fitted with Duracells. Took a screwdriver acting like a crowbar to yank out the dead yet stuck and leaky cells. Nasty. Princess Auto has a set of rather slim nail files in assorted shapes under their 'Powerfist' brand that is good to clean up contacts.

[keepread]

The first, dead battery is clearly a fake.
I took it apart, and the cells in it take about 5 seconds to charge from 1.6V to 2.1V, and there the charge ends. On a V-meter they show anywhere from 1.67 to 1.89V.
They feel too heavy, and on a digital scale they weigh 42 g whereas my known good li-ion cells weigh 28 g. Suspecting they are NiMH or NiCd even though they are stamped Li-ion 3.7V?