Keyword:     e.g.: Eee PC 1201N

Additional Options

Cheap laptop batteries > articles

What's mean Battery Cell Mismatch?

Cell mismatch can be found in brand-new as well as aged battery packs. Poor quality control at the cell manufacturing level and inadequate cell matching when assembling the batteries cause unevenly matched cells. If only slightly off, the cells in a new pack adapt to each other after a few charge/discharge cycles, like players in a winning sports team.

A weak cell holds less capacity and is discharged more quickly than the strong one. This imbalance causes cell reversal on the weak cell if the asus battery is discharged below 1V/cell. The weak cell reaches full charge first and goes into heat-generating overcharge while the stronger cell still accepts charge and remains cool. In both situations, the weak cell is at a disadvantage, making it weaker and contributing to a more acute cell mismatch condition. An analogy can be made with a high school bully who picks on the weaker kid.

High quality cells are more consistent in capacity than lower quality counterparts. During their life span, high quality cells degrade at about the same rate, helping to maintain the matching. Manufacturers of power tools choose high quality cells because of their durability under heavy load conditions and temperature extremes. Lower-cost cells have been tried, but early failure and consequent replacement is costlier than the initial investment.

The capacity matching between the cells in a camcorder battery pack should be within +/- 2.5 percent. Tighter tolerances are required on batteries with high cell counts that also must generate high load currents and are operating under adverse temperatures. There is a strong correlation between well-balanced cells and the longevity of a battery.
Lithium-based cells have tighter matching tolerances than their nickel-based cousins. Tight matching of all cells in a pack is especially important on lithium-based chemistries. All cells must reach the end-of-discharge voltage threshold at the same time. The full-charge point must be attained in unison by all cells. If the cells are allowed to get out of match, the weaker cell will be discharged to a lower voltage point before the cut-off occurs. On charge, this weak cell will attain the full-charge status before the others, causing the voltage to go higher than on the stronger cells. This larger voltage swing will put undue strain on the weak cell.

Each cell in a lithium-based pack is electronically monitored to assure proper cell matching during the fujitsu battery's life. An electronic circuit is added to some packs that compensate the differences in cell voltages. This is done by connecting a shunt across each cell string to consume the excess energy of the cells which are more energetic. The low-voltage cut-off occurs when the weakest cell reaches the end-of-discharge point.

The Li-ion HP Mini 110 battery is controlled down to the cell level to assure safety at all times. Because this chemistry is still relatively new and unpredictable under extreme conditions, manufacturers do not want to take undue risks. There have been a few failures but such irregularities are often kept a secret. This chemistry is considered very safe, considering the large number of Li-ion sony batteries that are in use.
more info: cheap laptop batteries

1. The Lithium Polymer Battery

2. Lithium Ion Notebook Battery Cells - What's Inside Notebook Batteries?

3. Laptop Computer Battery Power - An Overview of Laptop Batteries

4. Laptop Battery Chemistry 101 - Discount Laptop Batteries (Lithium Ion and Nickel Metal Hydride)

5. Laptop Batteries - How does a Laptop Battery work?

6. My new laptop and/or camcorder battery is not working at all! What's up?

7. Can I use my old version Ni-Cd battery charger to charge my Ni-MH batteries?

8. Does it really help to store batteries in the refrigerator?

9. What is the "Memory Effect"

10. The rating for battery

| Laptop Batteries| Camera Batteries &Chargers| Power Tool Batteries| Laptop AC Adapters| Mobile Phone Batteries| Laptop Keyboards| Laptop Screen| Laptop DVD| Laptop CPU Fan| Camcorder Batteries &Chargers|