11.1V 94Wh 55++ SL410 Laptop Battery for Lenovo ThinkPad

Functions very well good quality feels genuine fits in like normal w510, easy install. At most I get 2 hours battery charge which is better than nothing I have some protection in case the cable gets jostled now since the old battery is basically deteriorated into non-functionality

Was purchased for IBM T420 PC. Works grate including charge and discharge cycles. Tested with original IBM battery utility.

Normally I use a company called Kahlon for computer RAM upgrades and battery pack replacements. They didn't have this particular battery in stock so I matched the part number and the specifications on AliExpress and Amazon Business. This one was an exact match for a Lenovo ThinkPad T-420 and W-520. It is the higher powered model with the extra row of batteries attached to the rear of the battery. It fits and works perfectly and the price was a bargain. I would buy it again.

I run one ThinkPad W520 laptop 24/7 and another most of the day. Both are plugged into the AC adapter at all times. I know this is not good for battery longevity so I was looking for a cheaper battery than what Lenovo sells. This one was advertised as 94Wh but the ThinkVantage Power Manager 3 (PM3) utility reports design capacity at 86.58Wh, so about 92%. On the plus side, the cycle count is 0 (never used) and the manufacturing date is 8/26/2025, so just over 4 months old. PM3 says the batteries are Sanyo and the part number (FRU) is 42T4848. Battery appears to charge okay and I'll try to come back in a couple of months to report on how it's working.

Short-term review. Everything is relative. This is a battery designed for mid-range laptops made 12 years ago and battery tech has come a long way since then. These take a long time to charge up. That's a given. I bought this for my Lenovo Thinkpad T410. Great value laptop for the time and everything on it still works. If I put a movie on that is on the SSD or on a USB drive the battery will last about 140 minutes. If I play a Wifi streaming movie the time is cut down to about 90 minutes. Ethernet cable gives maybe 100 minutes. Yeah I know, kind of weird. Probably related to how much work the laptop has to do in the background while the same movie is being played. If you are using the laptop general productivity/office work and looking at video clips here and there the battery will last about 3 and a half hours. That's good for this battery+this old laptop!

no problem

Battery works, technically. Only the "top 25%" is usable. That is, the battery charges and discharges normally as far a sI can tell, but the laptop shuts off at 80% capacity. This IS better than the less than 5 minutes I get from the 12+ year old original battery, but I was expecting to have multiple hours of battery life(like I did previously when the original battery was newer).

The battery fit my laptop perfectly and actually is an upgrade that lasts longer than the factory battery that came with it. They got it to me super quickly as well.