Nickel-cadmium (NiCAD) – mature but has moderate energy density. Nickel-cadmium is used where long life, high discharge rate, and extended temperature range is important. Main applications are two-way radios, biomedical equipment, and power tools. Nickel-cadmium contains toxic metals.
Nickel-metal-hydride (NiMH) – has a higher energy density compared to nickel-cadmium at the expense of reduced cycle life. There are no toxic metals. Applications include mobile phones and laptop computers. NiMH is viewed as a steppingstone to lithium-based systems.
Sealed Lead Acid (SLA) invented in 1859 are the oldest type of recharge battery and are most economical for larger power applications where weight is of little concern. Lead-acid is the preferred choice for hospital equipment, wheelchairs, emergency lighting and UPS systems. Lead acid is inexpensive. Very short life in e-bike applications since they were not designed for high discharge. NOT environmentally friendly – highly toxic.
Lithium-ion manganese (LiMh) – the safest and fastest growing battery system for electric vehicle applications; offers high-energy density and low weight. Protection circuits needed to limit voltage and current. Applications include notebook computers, cell phones, cars, and e-bikes. High current versions are available for power tools and medical devices. Easy to recycle and reuse. Be careful with other types of lithium as some types are untested and have the potential for fires.
36 volt vs. 24 volt
36 volt systems boast faster speeds, quicker acceleration, greater range and better hill climbing capability than 24 volt systems. 24 volt systems are typically used on slower models that require pedal assistance to operate.
Recharging battery packs
Simply plug your battery pack into any standard 110-volt wall outlet. You can leave the battery pack on your e-bike or take it off on most models. Charging takes about four hours and costs just pennies per charge. Safety circuitry guarantees that the battery pack cannot be overcharged.
Maintaining battery packs
Plug in your battery pack after every use. Lithium batteries are memory-free batteries and do not require a full discharge before recharging.
Life of the battery pack
Lithium-ion manganese batteries typically can be fully charged and fully discharged 500 to 1000 times which translates to 10,000 to 20,000 miles with average usage. Lead Acid packs are only good for about 100 full charges.