NiCad (Nickel Cadmium) - This is the oldest technology and is the least prevalent today. NiCad batteries are prone to "memory effect" and are heavier than the newer technologies. NiCad is not environmentally friendly chemistry as it contains heavy metals that can not be disposed of in landfills. Most manufacturers have stopped producing batteries of this type of chemistry. As an end user, it will become increasingly difficult to source these batteries. The best alternative is external battery packs. This is an external battery, with run times of up to 10 hours and is compatible with most manufacturers.
NiMH (Nickel Metal Hydride) - These batteries are less likely prone to memory effect and have a much better power to weight ra
tio than NiCad. This is a commonly used chemistry. These batteries are also being phased out by most manufacturers. But many have lithium-ion versions that are compatible. Always consult the manufacturer or a reputable laptop battery supplier.
Li-Ion (Lithium Ion) - This will be the dominant technology because of its excellent power to weight ratio. Such considerations are becoming more important as mobile devices become smaller and lighter and battery weight becomes significant. Another plus point for Li-ion is that it does not suffer from memory effect at all. These batteries have a tendency to lose charge quickly towards the end of their effective life. If this starts to happen, the battery needs replacing.
These three technologies are very different in how they charge and therefore should not be substituted unless the device is designed to take different chemistries. The training manual will describe which batteries suitable. Lithium ion laptop batteries found at ComputerBatteries.co.uk
Laptop
Laptop batteries are rated by, Voltage (V) and milli-hours (mAh). Voltage is the rate at which energy is drawn from the battery and milliamps-hours represents the capacity of the battery. The milliamps hour rating corresponds to the running time on battery. A battery with a high milliamps hour rating, has a relatively longer running time than a battery with a low milliamps hour rating.
Batteries with different milliamps hours can be used on the same laptop provided voltage is the same. The voltage rating has to match the original battery or as recommended by the computer manual. Use a battery with a different voltage setting can seriously damage laptop. The power ratings of most compatible / replacement batteries are higher than the original manufacturers' batteries. This will not damage your laptop, in reality, it just means that these batteries often last longer than original manufacturers' batteries. Ask the experts like PowerUp on compatible replacement laptop batteries.
Sometimes when a laptop battery will vary on individual notebook computers, based on the applications used (i.e. high graphics, games), the number of times something is saved or retrieved from the hard disk and / or CD-ROM drive, memory notebook, and chemistry and capacity of the battery. A 'realistic' average run-time of a battery is 1.5 to 3 hours. Using devices like a wireless adapter on the laptop also drains the battery considerably.
The life of a battery during normal usage is around 500 to 900 charge-discharge cycles. It is about one and half to three years of battery life for the average user. As the rechargeable battery begins to fail, operating time of battery starts to decline. See the Laptop Battery & AC Adapter Information page for advice from powerup.
Laptop
Most laptop batteries when purchased are sent out in a discharged state. The laptop batteries require to be "run them" to achieve maximum performance and the best lifetime. Simply insert the battery into your laptop and makes it possible to charge fully and then discharge the battery (i.e. run your laptop using battery power until it shuts off) then charge the battery again.
It is possible that when you first put the new battery in your laptop will show it is fully charged almost immediately, but it does not flow to the laptop for very long. This does not mean that the battery is faulty, simply take out and reinsert the battery, fully charge it again and this should solve the problem.
It may take some time for certain laptops to recognize new batteries, and you may have to run a calibration program that you can access via the control panel on your laptop. If in doubt please consult your user manual for your laptop.
Make sure you discharge the battery from time to time, as this will prolong the useful life of the battery. To not use the battery for a while (maybe a month or more), remove it from your laptop into a fully charged state and store in a cool dry place away from heat and light.
Listed below are tips to ensure optimal battery life:
Use the AC adapter when it is possible.
Insert the Windows Power Management settings to maximum savings.
Lower the brightness setting on the screen backlight.
Disconnect any unused devices (e.g. modems) when not needed.
Use power management freeware like Power Center 2.12.
Disable Auto Insert Notification on the CD-ROM.
Turn off Autosave features.
Disable automatic formatting, spelling and auto recalculate functions.
Use disk caching programs such as Norton Utilities to lower disk access time.
Add RAM to lower disk access time.
If you have a backup battery, use it in rotation with the current battery.
Using standby or hibernation mode when you take a break.
Fully drain and recharge the battery with a couple of months.
Minimize the number of programs running simultaneously.
Use smaller programs when possible (e.g. WordPad versus Word).
Minimize games and DVD viewing.
