Batteries for power tools and other industrial devices can often be repaired by replacing one or all cells. Finding a NiCd and NiMH cell is relatively easy; locating the correct Li-ion cell can be more difficult.

1. How to Repair a Battery Pack | Battery Wiki
Written by batteryfast.com
Wednesday, 29 June 2011 02:58 -
How to Repair a Battery Pack | Battery Wiki
Batteries for power tools and other industrial devices can often be repaired by replacing one or
all cells. Finding a NiCd and NiMH cell is relatively easy; locating the correct Li-ion cell can be
more difficult. Naked Li-ion cells are not readily available off the shelf and a reputable battery
manufacturer may only sell to certified pack assemblers. Incorrect use or lack of an protection
circuit could cause stress and disintegration of the replaced cell. When repairing a Li-ion pack
make certain that each cell is properly connected to a protection circuit. Read about Safety
Concerns and Protection Circuits.
If a relatively new pack has only one defective cell, you may replace only the affected cell. On
an aged battery , it’s best to replace all cells. Adding a new cell with full capacity in between
neighboring cells that have faded would cause a cell mismatch. Matching the replacement cell
with one of a lower rating may work but this fix is often of short duration. Always replace with the
same chemistry cell.
A well-matched battery pack means that all cells have similar capacities. An anomaly can be
1/4

2. How to Repair a Battery Pack | Battery Wiki
Written by batteryfast.com
Wednesday, 29 June 2011 02:58 -
drawn with a chain in which the weakest link determines the performance of the battery. Read
more about Can Batteries Be Restored?.
When replacing all cells, the rating is less important as long as the differences are not too large
for the charger to handle. Cells with higher Ah will simply take a bit longer to charge. The
state-of-charge of all cells being charged for the first time should have a similar charge level,
and the open-circuit voltages should be within 10 percent of each other
Many visitors ask if NiCd can be replaced with NiMH? Theoretically, this should be possible but
charging may be an issue. NiMH uses a more defined charge algorithm than NiCd. A modern
NiMH charger can charge both NiMH and NiCd; the old NiCd charger could overcharge NiMH
by not properly detecting full charge state and applying a trickle charge that is too high.
Welding the cells is the only reliable way to get dependable connection. Limit the heat transfer
to the cells during welding to prevent excess heat buildup.
Simple Guidelines when Repairing Battery Packs
- Only connect cells that are matched and have the identical state-of-charge. Do not
connect cells of different chemistry, age or capacity.
- Never charge or discharge Li-ion batteries without a working protection circuit
unattended. Each cell must be monitored individually.
- Include a temperature sensor that disrupts the current on high heat.
2/4

3. How to Repair a Battery Pack | Battery Wiki
Written by batteryfast.com
Wednesday, 29 June 2011 02:58 -
- Apply a slow charge only if the cells have different state-of-charge.
- Pay special attention when using an unknown brand of cells. Some may not contain a high
level of intrinsic safety.
- Li-ion is sensitive to reverse polarization. Observe correct polarity.
- Do not charge a Li-ion battery that exhibits physical damage or has dwelled at a voltage
of less than 1.5V/cell.
- When repairing Li-ion, assure that each cell is connected to a protection circuit.
Other Business News:
- Acer aspire 5920 battery
- Acer as07b31 battery
- Hp 484170-001 battery
- dell latitude d630 battery
CloudTag: Repair , Battery Pack , Battery Wiki , Acer aspire 5920 laptop battery , Acer
as07b31 laptop battery
,
Hp 484170-001 laptop battery
,
dell latitude d630 laptop battery
Battery Wiki Related Articles:
- Tablet wars: Amazon readies tablet, RIM lowers PlayBook estimates, iPad rolls on
- Laptop Battery Life Problems | Battery Wiki
- Best Travel Laptops for 2011
- Mozilla's Firefox 5 Goes Live, First Rapid-Release Version
3/4

4. How to Repair a Battery Pack | Battery Wiki
Written by batteryfast.com
Wednesday, 29 June 2011 02:58 -
- Troubleshooting and Maintenance Your Laptop Battery | Battery Wiki
- Top 10 Easy Steps for a longer Your battery life | Battery Wiki
- Battery Wiki - Tips to make your Laptop Lithium Battery Lasts longer
- How To Choose the Dell Inspiron E1505 laptop battery and Care Tips
- Internal Battery Design | Battery Wiki
4/4