Secondary Batteries

Secondary Batteries

Secondary batteries are the rechargeable batteries. Theyhave the advantage of being more cost-efficient over the long term,although individual batteries are more expensive. Generally,secondary batteries have a lower capacity and initial voltage, aflat discharge curve, higher self discharge rates and varyingrecharge life ratings. Secondary batteries usually have more active(less stable) chemistries which need special handling, containmentand disposal. Ni-Cd and small-size lead acid batteries requirespecial disposal and should not be simply thrownaway.

Advantages

Best solution for high drain applications

For high utilisation applications the cost of the chargeris soon paid back.

Shortcomings

Cost of charger. For low cost applications such as toysthe charger could cost much more than the product itsupports.

Safety issues with mains power.

Lower energy density than primary cells unless exoticchemistries used.

Lack of standards

Many custom pack designs and limited interchangeability.(Disadvantage for the user but creates a captive aftermarket forthe manufacturer)

Applications

Traction

Power tools

Motor drives

Laptop computers

Mobile phones

PDAs

Camcorders

Toys

Typical Battery Chemistries

Alternatives

Lead Acid

Lithium

Nickel Cadmium (NiCad)

Nickel Hydrogen

Nickel Iron (NiFe)

Nickel Metal Hydride (NiMH)

Nickel Zinc

Zebra

See also Primary Batteries