Types of laptop batteries:

Nickel-cadmium (NiCd) batteries: These were first manufactured batteries for laptops. They were relatively cheap, had high performance and versatile because they are used in a variety of products. However, NiCd batteries have now been abandoned by laptop manufacturers with the introduction of more efficient and lighter batteries.

Nickel-Metal Hydride (NiMH) batteries: NiMH was a big improvement on the current – Performance, reliability, efficiency, safety and capacity. The "memory effect" was the only issue with NiMH batteries, which require that they be discharged completely before recharging to gain the highest performance. These batteries are still found in older laptop models.