Not Green Cell, but I got a 6 cell replacement from GHU for my T440s workhorse. For the first week, it reported 9+ hours on a charge. Super cool, I thought, I can basically work outside as long as I like. The second week it went down to 2 hours on a full charge. 50USD down the tubes. I'll pay the premium for OEM batteries from now on. This, of course, was just my experience, but reviews suggest it is a common one. I just thought it would be worth the risk.
ThinkPad
IBM and Lenovo ThinkPad laptop enthusiasts!
The OEM route is tempting me too to be honest but at the same time Lenovo doesn't make those batteries anymore and those that you'll buy would have been in their storage for years.
Ifixit sells very repuatble battery replacememts, i have one for my t440p! If ifixit doesnt sell it inland (microcenters brand) batterys work well and i have never had any issues with either.
For how long did you have that battery?
i bought one from ifixt 1 year ago 9cell for my w540 and this Christmas i bought a 6cell, and ive had and used both. the 9 cell gives me 8hours of battery of medium usage, web browsing, word processing and such.
As a data point, I have a Green Cell battery in my X220. I have bought the battery on July 24, 2022 and I have been using my X220 regularly but lightly. The battery was marketed as 6600 mAh at 10.8 V. As of writing, the OS reports design capacity of 73.26 Wh and current capacity of 60.6 Wh:
POWER_SUPPLY_NAME=BAT0
POWER_SUPPLY_TYPE=Battery
POWER_SUPPLY_STATUS=Discharging
POWER_SUPPLY_PRESENT=1
POWER_SUPPLY_TECHNOLOGY=Li-ion
POWER_SUPPLY_CYCLE_COUNT=0
POWER_SUPPLY_VOLTAGE_MIN_DESIGN=11100000
POWER_SUPPLY_VOLTAGE_NOW=11783000
POWER_SUPPLY_POWER_NOW=28726000
POWER_SUPPLY_ENERGY_FULL_DESIGN=73260000
POWER_SUPPLY_ENERGY_FULL=60600000
POWER_SUPPLY_ENERGY_NOW=54960000
POWER_SUPPLY_CAPACITY=90
POWER_SUPPLY_CAPACITY_LEVEL=Normal
POWER_SUPPLY_MODEL_NAME=45N1023
POWER_SUPPLY_MANUFACTURER=SANYO
POWER_SUPPLY_SERIAL_NUMBER= 9001
So 82.7% left after 1.5 years, that's cool I think!
(especially given that they offer only a 12 months warranty)
X220 uses 18650-cells, which are superior. Either he uses it always on charger or the cells are really bad quality.
Nevertheless, has nothing to do with your T480 since it has LiPo batteries, not 18650-celled.
No idea about green cells. I've done ok with Dr. Notebook batteries from battdepot.com.