07-10-2019 02:25 AM
I acquired a T480 last month which by design operates on two batteries (1 - internal 24Wh; 2 - external 72Wh). One of the first odd behaviours I observed was battery 1 won't charge beyond 80% and only charge battery 2.
As with observation notes put on the reddit post, I then further witnessed battery 1 continues charging only after battery 2 was full. During that period, the laptop only consumed battery 2 while leaving battery 1 as an "emergency reserve fuel tank", leaving me to ponder just how healthy is that. But a few days later the roles were reversed with battery 1 depleted first before transitioning to "reserve tank" battery 2. And as of now, it has swapped over the original sequence with the laptop refusing for weeks to use battery 1 until battery 2 depletion.
Lenovo Vantage only offers to define charge threshold parameters, and does not offer control over any sort of battery consumption pattern. So what is the exact logic that the laptop has been programmed with to handle multiple battery consumption?
Solved! Go to Solution.
08-20-2019 11:34 AM - edited 08-21-2019 09:24 AM
Today I bought a new battery model 61 (flush slim, 24Whr), after undergoing a gauge reset procedure, I see the laptop swap over to internal battery 1. It does not attempt to use the fully-charge new battery 2.
From my observations, it appears the laptop favours the battery with the most cycles (older).
Is it me or does the battery selection logic appear counter-intuitive?
08-23-2019 12:28 AM
08-28-2019 07:48 AM
Funny how the technician's advice to "just search the Internet" only resulted in pages after pages of customers complaining about the lousy Lenovo battery consumption policy. With that I happened to dig up an older thread with the discovery of the actual logic - tested and verified with my laptop -
Summary: whichever battery that has the better wear ratio (i.e. Full-charge capacity / Design capacity), not by mere charge cycles, will be used repeatedly until it deteriorates to a level worse than the other battery, of which that other battery will be likewise be used until it gets worse, and on, and on.
Bravo, Lenovo, bravo. Trying to push for more customers to collapse their internal batteries?