IBM ThinkPad X20 Series Battery are made from a grade cells and highest quality parts,the IBM laptop battery are tailored made according to the original size,
whether the battery appearance, size and quality are the same as with the
original. Every IBM ThinkPad X20 Series laptop battery should be under strict quality
control including filtration and safety testing of voltage,capacity and
battery core before leaving the factory, and has passed the authentication
of CE, UL, EMC, CQC,ROHS, etc.

IBM ThinkPad X20 Series batteries features:

100% Q.C. of Our IBM THINKPAD X20 SERIES Laptop batteries.
100% OEM Compatible Meet or exceed OEM THINKPAD X20 SERIES specifications.
Only the highest quality cells are used in our IBM laptop notebook batteries

Replacement battery Compatible Part Number:
02K6651,02K6678, 02K6712, 02K6837, 02K6838, 02K6839,
 02K6850, 02K6852, 08K8024, 02K6653, 02K6678, 02K6679,
02K6710, 02K6758, 02K6759, 02K6760, 02K6761, 02K6845,
02K6846, 02K6854, 08K8024, FRU 02K6652, FRU02K6653

Replacement Fit Models:
IBM
IBM ThinkPad X20 Series
ibm ThinkPad X20 2660-XXX, ThinkPad X20 2661-XXX
ThinkPad X20 2662-XXX

IBM ThinkPad X21 Series
ibm ThinkPad X21 2660-XXX, ThinkPad X21 2662-XXX

IBM ThinkPad X22 Series
ibm ThinkPad X22 2660-XXX, ThinkPad X22 2662-XXX

IBM ThinkPad X23 Series
ibm ThinkPad X23 2660-XXX, ThinkPad X23 2662-XXX

IBm ThinkPad X24 Series
ibm ThinkPad X24 2660-XXX, ThinkPad X24 2662-XXX

Specification:
Battery Type: Li-ion,  Voltage: 10.8V,  Capacity: 4400mAh



We should care IBM THINKPAD X20 battery To Get The Maximum Life Out Of It. It's a valid question calling for special attention since laptop batteries are usually expensive to replace.
First of all, how long should your battery last? 2-4 years is generally acceptable depending on how frequently you use and charge the battery. If you travel a lot and use and charge your battery frequently then you might only get a couple of years at the most out of your laptop battery.
IBM THINKPAD X20 battery are usually made with batteries. They also have a self-discharge rate of about 1% per day so you need to be sure to charge them at least once a month.
So how can you care for your battery to get the maximum life out of it?
Your new IBM THINKPAD X20 laptop battery comes in a discharged condition and must be charged before use (refer to your computer manual for charging instructions).
When charging IBM x20 battery for the first time your computer may indicate that charging is complete after just 10 or 15 minutes. This is a normal phenomenon with rechargeable batteries. Simply remove the battery from the computer and repeat the charging procedure.
Charge up completely, even if the battery isn't fully discharged, don’t run out of your IBM THINKPAD X20 Laptop Battery. laptop batteries work best when they are recharged while they still have 10 to 20% capacity remaining. So if you are using your notebook battery on your journey, try not to get in the habit of using the notebook battery until it has almost no charge.
Recharge the battery in your notebook using the AC adapter, whether the notebook is on or off.
When carrying the battery. Do not short circuit the terminals or store your battery pack with metal objects such as necklaces or hairpins.
Double your work time available without having to plug in to AC power.
Do not disassemble the Battery, the contents may be corrosive and harmful for your health.
If your IBM THINKPAD X20 Laptop Battery will not be in use it should be removed from your laptop and stored in an Anti-Static bag and in a dry, cool place.

IBM x20 battery tips