Please ensure the product(s) that you are going to buy fits the brand, model and part number of your device.

Specifications:

Battery Type: Li-ion
Voltage: 10.8 V
Battery capacity: 4400 mAh
Color: Black
Demension:

Replace battery part number:

LENOVO
42T4235
42T4731
42T4733
42T4737
42T4753
42T4757
51J0499
ASM 42T4703
ASM 42T4752
ASM 42T4756
ASM 42T4796
FRU 42T4702
FRU 42T4751
FRU 42T4755
FRU 42T4791
FRU 42T4793
FRU 42T4795
FRU 42T4797
FRU 42T4817
FRU 42T4819

This battery is also compatible with the following models :

LENOVO
ThinkPad E40
ThinkPad E50
ThinkPad Edge 0578-47B
ThinkPad Edge 14"
ThinkPad Edge 14" 05787UJ
ThinkPad Edge 14" 05787VJ
ThinkPad Edge 14" 05787WJ
ThinkPad Edge 14" 05787XJ
ThinkPad Edge 14" 05787YJ
ThinkPad Edge 15"
ThinkPad SL410 2842
ThinkPad SL410 2874
ThinkPad SL410 series
ThinkPad SL410k 2842
ThinkPad SL510 2847
ThinkPad SL510 2875
ThinkPad SL510 series
ThinkPad T410
ThinkPad T510
ThinkPad T510i
ThinkPad W510

laptop batteries have two main ratings on them: Volts and Amperes. Because size and weight of laptop batteries is limited when compared to larger batteries such as car batteries, most companies show their ratings with Volts and Milliamperes. One thousand Milliamperes equals 1 Ampere. When buying a battery, select batteries with the most Milliamperes (or mAh). Batteries are also rated by Watt-Hours, perhaps the simplest rating of all. This is found by multiplying the Volts and the Amperes together. For example:

14.4 Volts, 4000mAh (Note: 4000mAh is equal to 4.0 Amperes).

14.4 x 4.0 = 57.60 Watt-Hours

Watt-Hours signifies the energy needed to power one watt for one hour. This laptop battery can power 57.60 watts for one hour. If your laptop runs at 20.50 watts, as an example, this laptop battery could power your laptop for 2.8 hours.

There are several steps you can take to help you get maximum performance from your laptop battery:

Prevent the Memory Effect - Keep the laptop battery healthy by fully charging and then fully discharging it at least once every two to three weeks. Exceptions to the rule are Li-Ion batteries which do not suffer from the memory effect.

Keep the laptop Batteries Clean - It’s a good idea to clean dirty battery contacts with a cotton swab and alcohol. This helps maintain a good connection between the battery and the portable device.

Exercise the Battery - Do not leave the battery dormant for long periods of time. We recommend using the battery at least once every two to three weeks. If a laptop battery has not been used for a long period of time, perform the new battery break in procedure described above.

Battery Storage - If you don’t plan on using the laptop battery for a month or more, store it in a clean, dry, cool place away from heat and metal objects. NiCad, NiMH and Li-Ion batteries will self-discharge during storage; remember to recharge the batteries before use.

Upgrade my 42T4702 LENOVO ThinkPad SL410 SL510 ASM 42T4703 battery from NiMH to Li-Ion

NiCad, NiMH and Li-Ion laptop batteries are all fundamentally different from one another and cannot be substituted unless the laptop has been pre-configured from the manufacturer to accept more than one type of battery chemistry. Please refer to your manual to find out which rechargeable battery types the laptop device supports or use our Battery Finder above to find all the compatible laptop batteries for your device. It will automatically list all of the battery chemistries supported by your specific device. If your device does allow you to upgrade the battery from NiMH to Li-Ion, you will typically get longer run times.

For example, if your laptop uses a NI-MH battery that is 9.6 Volts, 4000mAh and the new li-ion laptop battery is 14.4 Volt, 3600mAh, then you will obtain longer run time with the li-ion battery.

Example.

Li-Ion: 14.4 Volts x 3.6 Amperes = 51.84 Watt Hours
Ni-MH: 9.6 Volts x 4 Amperes = 38.4 Watt Hours
The Li-Ion is stronger and has longer run time.