MegaBatteries.com - Rechargeable Batteries and Chargers Mega Center

Battery Info

The Information below will help you make the correct decision when purchasing Rechargeable batteries. Please contact us if you have any questions or comments.

Battery Definitions

Ni-Cd – Nickel Cadmium batteries are an older technology; however they have some very good characteristics. These batteries have a longer shelf life as they do not discharge as quickly as NiMH batteries after being charged. Using today’s battery charger technology these batteries are quicker to charge as they have a lower capacity. These batteries typically will give you around 500 life cycles. The price is very attractive and they are perfect for low drainage devices. The down side to these batteries is that they have a “Memory Effect”. This effect will occur if you partially use the battery and then charge it. This will cause the battery to have fewer life cycles. If you discharge the battery before using it, then this problem will not occur. Nicad batteries are still very popular in cordless phones, RC vehicles, solar lights, remote controls, clocks, hand held radios and much more.

Ni-MH – Nickel Metal Hydride is a newer battery technology. Many of the old Nicd batteries are now available in NiMH. These batteries have a much higher capacity then Nicd, so your device will have a much longer run time in between charges. NiMH batteries do not have a “Memory effect” so you can charge them even if they have only been used a bit. They are more expensive then Ni-CD, however you can typically get around 1000 life cycles. These batteries are also more environmentally friendly as they have nothing harmful in them. They are best used in high draining devices; Digital Cameras, Children’s toys, Walkmans, Discmans, Cellular phones, flash lights and more.

LI-ON – Lithium Ion is the newest battery chemistry that exists today. Lithium Ion rechargeable batteries can be just as high in capacity and in most cases higher then Ni-MH batteries. LI-ON batteries are only available in laptop and cellular phone batteries. Lithium Ion batteries are smaller and lighter in weight than Ni-MH batteries. They do not have “memory effect” and are more expensive.

Battery Terminology

Amp Hours (Ah) – Refers to the amperage – the strength of the electrical current expressed in amperes that the battery can hold. The higher the Ah, the longer the battery will last in-between charges (See mAh Below).
Capacity – Measured in Amp Hours (Ah) or Milliamp Hours and is the amount of time the battery can supply the necessary voltage.
Cell – One individual battery.

Charge – With the use of a charger, charging a battery will insert energy into it.

Condition – The process by which a battery is discharged and charged in order to guarantee maximum performance.

Discharge – The process of taking energy out of a battery.

Life Cycle – The amount of times a battery can be charged and discharged before it no longer has any power.

Memory Effect – The Effect that represents the decrease in capacity and voltage in Ni-Cd batteries due to repetitive charging and incomplete discharging. This results in loss of run-time in-between charges. Ie: If 50% of a Ni-CD battery is consistently used and then charged, the battery will eventually forget that it isn’t discharged all the way and will only be functional at 50% capacity

Milliamp Hours (mAh) – Applies to how much energy the battery can store (capacity of the battery). The higher the mAh, the longer the battery will last before needing to be charged. One mAh is the equivalent to 1/1000 Amps. IE: 2.5 Ah = 2500 mAh.

Self-Discharge – If batteries are fully charged and sit on the shelf for one-two months, they will Self-Discharge. By Self-Discharging, the batteries will lose capacity on their own when not being used in a device.