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
Color:  dark grey
Dimension:  158.50x79.8x21.3 mm
Capacity:  4400.00mAh
Volt:  11.10 V
Replace battery part number: 
805N00006 UN258
258-4S4400-S1S1 258-4S4400-S2M1
258-4S4400-S1P1 63-UD7021-00
63-UD7022-0A 63-UD7022-1A
63-UD7022-3A NBP001374-00
NBP001385-00 NBP001390-00
NBP001395-00 SA2004801
23-UD7010-0F 23-UD7110-1B
258-3S4400-S1S1 258-3S4400-S2M1
2584S4400S1P1 2584S4400S2M1
F01 F04 
   
 
This battery is also compatible with the following models : 
ABS Mayhem G1
ACMA Elite N258KA
AMAX Elite N258KA

AVERATEC 6100 Series
AVERATEC 6128, 6128H
AVERATEC 6130, 6130H
AVERATEC 6130H1, 6130HS

AVERATEC AV6128H1-10
AVERATEC AV6130H1-10, AV6130HS-20

CYBER POWER Xployer X5-4000
CYBER POWER Xployer X5-5000
CYBER POWER Xployer X5-6000

ELEMENTS U-258
Fujitsu Amilo A-1630
Fujitsu Amilo A1630
Fujitsu Amilo D-1840 Fujitsu Amilo D1840
Fujitsu Amilo D-1845 Fujitsu Amilo D1845
Fujitsu Amilo A-1630 Widescreen Fujitsu Amilo A1630 Widescreen

MAX GROUP MaxNote 9064
MAX GROUP MaxNote 9258
MAX GROUP MaxNote U-258KA
MAX GROUP MaxNote U-258KO

MICRON Transport T3000
MICRON Transport X3000 MICRON Transport X3100
MPC TransPort T3000
MPC TransPort X3000, X3100

MWAVE Mwave N258KA
PC CLUB EnPower ENP 75803 Mythos Trito
PC CLUB EnPower ENP75803 Mythos Triton
PC CLUB Enpower Mythos Triton
SUPER TALENT N258SAX
TATUNG N258SA

UNITED MICRO N258KA
UNITED MICRO N258KAO
UNITED MICRO N258KAX
UNITED MICRO N258SA

UNIWILL N258
UNIWILL N258AS, N258AX
UNIWILL N258KA, N258KAO
UNIWILL N258SA, N258SAO
UNIWILL N258SAU, N258SAX

XTERASYS XteraNote N258
XTERASYS XteraNote N258KA

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 ADVENT CBI0834A N34AS1 N34AS2 N35AS N35BS2 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.