Model: 36V Bottle Battery
Capacity: 9Ah or 11.6Ah
2c rating, Motor usage < 500W
This kit includes all fittings and charger.
Lithium ion batteries are far superior to lead acid batteries and are clearly the ideal choice for use with an electric bike. There is a range of chemistry used in lithium ion batteries but the best used chemistries for electric bicycles are lithium iron phosphate (LiFePO4) and lithium manganese (LiMn). LiFePO4 has advantages of being the safest and longest lasting, while LiMn has a higher power to weight ratio, sleeker designs and also very high life time. Lithium ion batteries last about 3 to 5 times as long as lead acid batteries and weigh about three times less - approximately 4kg (Li ion) vs 12kg (lead acid) for 36V 10ah. There is simply no comparison if you are looking for high performance. The cost is still very high for excellent quality lithium ion battery packs for electric bicycles but the greatly enhanced lifespan easily compensates for this cost difference. It is important to use a lithium ion battery designed for an electric bike as they have battery management systems inside them to limit excessive discharge, control maximum discharge rate and balance charge between cells when charging. Click_here to download a PDF file with more information on lithium ion batteries, including correct charging procedures and care and maintenance tips.
Lithium ion batteries for electric bicycles must be specifically designed due to the presence of a battery management system (BMS) within the pack. This piece of circuitry must be set appropriately to control the amount of current draw required by the motor and to limit excessive discharge capacity. The BMS is also important for balancing cell charge between the individual cells within the battery to maintain battery life over time. For performance reviews of the batteries on offer please read through some of the testimonials.
Sealed lead acid batteries are also not a bad option if that is what you have handy or are budget limited. They have proven through the test of time and handle the current draw of electric bicycle motors well. Absorbent glass mat (AGM) batteries are commonly used lead acid batteries for electric vehicles, they use either gel or absorbant glass mat fibres to hold the electrolyte. They have a higher energy density than typical car batteries and can be inverted without spilling acid, they cope with higher temperatures and can be charged and discharged more rapidly. You should be able to get a set of sealed lead acid batteries from a local battery shop for between $130 - $250. If running a 36V motor, you will need to get three 12V batteries and hook them up in series (aim for about 12ah each battery). You will also need to get a 36V battery charger - send us an email if you need help in sourcing one as they can be difficult to come by.
Lead acid batteries suffer in comparison to lithium ion batteries on two important factors. Recharge times and weight. Lead acid batteries can be recharged approximately 200-300 times while high-end lithium ion batteries can be recharged over 1000 times. Lead acid batteries are also about three times as heavy. We're sorry to those who would prefer to use lead acid batteries or purchase some for their old kit. We've opted to aim for high-end products and no longer stock them. The battery is the most expensive component of our kits, approximately three quarters of the cost. You will rarely find any commercial kit that uses LiFePO4 batteries, they all tend to use lead acid, nickel metal hydride or inferior lithium ion chemistry. We can only imagine this is for future sales reasons as the batteries will perish within a year or two and you will be forced to purchase another one. It is very important with any battery that you keep it as charged as possible as often as possible. Running a battery flat will damage it if done more than a few times and you will notice that the range noticably decreases. We recommend putting the battery on the charger when you get home from work in the evenings and then disconnecting it after a few hours when fully charged. If you are not using your bicycle during the winter months then charge it every month or so anyway to maintain and extend its life. Please note that you must not use a lead acid battery charger with lithium ion batteries!