If you have an electric bike its lifeblood is the electric batteries, it is the most important components of an electric bike. If you have a crappy batteries, your bike will give you a headache. Battery technology is evolving rapidly, so it’s hard to know what type of battery is best.
Here’s a guide to battery types for electric bikes:
Lead-acid Electric Bike Batteries or SLA - these batteries are sealed in a hard plastic case and can be turned in any orientation safely without leaking acid which makes them good for ebike use. They are cheap and easy to recycle. Lead acid batteries also has high power output unlike Lithium batteries that generally don’t like to handle too much current.
The downside for this is they are usually large and heavy, that limits where you can place them on your ebikes. They are also sensitive to bad treatment, and have a short lifespan about less than 200 cycles.
Since SLAs are heavy, it's advisable to mount your batteries as low as possible to keep the center of gravity of the ebike lower towards the ground. This will significantly improve your bike's handling.
Lithium Electric Bike Batteries - the best advantage of lithium batteries is their small size, you can fit them almost anywhere in your ebike frame and they are lightweight. Since they are small you can fit 2 or 3 mid to large capacity lithium batteries in your bike that can give you more range.
Lithium batteries that are designed specially for ebikes often come with specific bicycle mounting points that makes them very easy to attach to the bike frame, seat post or rear rack.
The big disadvantage of these batteries is the cost, they are much more expensive than lead acid batteries. Prices vary depending on the voltage and capacity of the lithium battery, but standard ebikes usually have lithium batteries starting in the $400 range. Another disadvantage is they are easy target for thieves since they are small and has a high price tags in the black market.
Types of lithium bike batteries includes:
Lithium Iron Phosphate (LiFePO4) - most expensive lithium batteries, they last longer than others and also the safest.
Lithium Manganese Oxide (LiMn2O4) and Lithium Nickel Manganese Cobalt Oxide (LiNiMnCoO2) - LiMn2O4 and LiNiMnCoO2 batteries fall into the mid range of lithium batteries in terms of size, weight, safety, lifespan and cost.
RC Lithium Polymer batteries (RC LiPo) - thase are the smallest, cheapest, lightest and most powerful lithium batteries. Unfortunately, they don't last long and can explode if not handled correctly.
Nickel-cadmium (NiCd) Electric Bike Batteries - type of rechargeable battery using nickel oxide hydroxide and metallic cadmium as electrodes. They have more capacity than lead-acid battery. However, nickel- cadmium is expensive and cadmium is a pollutant and hard to recycle which is bad for the environment.
Nickel-metal Hydride (NiMh) Electric Bike Batteries - they are more efficient than NiCd batteries and more expensive.