Battery options for ThinkPad T420S

I just got my new T420s and while it's thin and light enough for me, the 3 hr battery life just doesn't cut it for my needs.

So, I need a bigger battery.

Is this the only option?

Lenovo Ultrabay 3-cell battery ( 57Y4536 )
https://www.lapstars.de/product_info.php?cPath=393_395&products_id=4884
- Goes into the optical drive slot and replaces the ODD. Increases capacity circa 50% from the original 6-cell battery when the two are combined, hopefully giving roughly 4.5 hours of battery life.

I read somewhere that this model would "stick out" from the ODD bay slot?

Is this true? I'd rather not have a hunchback at the side of the laptop.

Has anybody tried this model with the T4 20 S?

Thanks in advance for all the info on this!

 

For the same price you can get second 6cell battery witch will give more battery lifetime than 6cell+mediabay if swapping batteries is not a problem for you it can be good solution.

 

The 3 cell battery does not stick out and should increase your run time by about 2/3rds (eg 3 hours to 5 hours). However, 3 hours isn't very good for your main battery alone and up to 5 hours is feasible with some tweaking as long as you aren't doing anything which uses significant power (eg anything connected to USB causes a noticeable increase in the power drain).

Also, the previous generation bay batteries (P/N 43R8891 / 43R8890) work fine and are easier to find at a more reasonable price, but have slightly lower capacity.

John

 

To follow up on that last post, the previous generation batteries are sold under other part numbers also (one of mine is a 41U4890, the other is 42T4679, both 10.80V 2.7Ah),I think the year of manufactuer is cocded into the FRU part number (my guess is 41 is for 2007, 42 for 2008, maybe John can confirm 43 is 2009?), one of mine is used from from 2007 with 76% capacity left after about 90 cycles, the other from 2008 is new still rated at 100% capacity, I paid $30-$40 for them on ebay. I can confirm these work and are the 29Wh (10.80V 2.7Ah) batteries sold for the T61, as well as other models. (the current #42 battery you posted a link to is rated at 32 Wh), there is also an older even lower capacity (23Wh?) battery that looks the same, but I can't confirm it works in the T420s. If buying older/used batteries off ebay, etc. be ware of ones marked IBM instead of Lenovo, those would be older batteries built before the Lenovo Thinkpad buyout in 2005.

Ike

 

The physical issue mentioned in other threads is that the battery does not sit flush with the T420s and has a bit of wiggle to it. The flush is not that it sticks out, but that it isn't angled down like the laptop at the bottom 1/8". Neither are terribly important.

The main battery, for me, lasts around 4 hours. The bay battery brings me to 6-9 hours depending on how hard I push the CPU. I run on Power Source Optimized defaults except display brightness at 5 and turned off sleep.

To me it has all the benefits of the X220 but trading the ultrabay for a 14" display with HD+ resolution.