Electric bicycle

The application of batteries in electric bicycles has undergone an evolution from lead-acid batteries to the popularization of lithium batteries, and then to the exploration of new battery technologies. Currently, it is developing towards high energy density, intelligence, and safety. The following analysis will focus on battery types, technical characteristics, application cases, and development trends:

1、 Mainstream battery types and their technical characteristics
Lead acid battery
Advantages: Low cost, mature technology, suitable for price sensitive mid to low end markets.
Disadvantages: Low energy density, short cycle life (about 300-500 times), heavy weight, and susceptibility to low temperatures, resulting in significant range degradation.
lithium battery
Types: including lithium iron phosphate (LFP), ternary lithium (NCM), etc.
Advantages:
High energy density: Under the same volume, the endurance of lithium batteries is 2-3 times that of lead-acid batteries.
Long lifespan: The cycle life can reach 1000-2000 times, with low maintenance costs.
Lightweight: Only one-third the weight of lead-acid batteries, improving vehicle handling.
Disadvantage: High cost and risk of thermal runaway in extreme situations (although regular products have been effectively controlled through BMS systems).
sodium-ion batteries
Advantages:
Low cost: With abundant sodium resources, the cost of raw materials is reduced by about 30% compared to lithium batteries.
Excellent low-temperature performance: Even at -20 ℃, the discharge efficiency can still reach over 90%.
Strong fast charging capability: Supports 2C fast charging (charging to 80% in 30 minutes).
Disadvantage: The energy density is slightly lower than that of lithium batteries, and it is currently mainly used in mid to low end car models.
Graphene battery
Advantages: By adding graphene material to lead-acid batteries, the cycle life (about 500 cycles) and low-temperature performance are improved, while the cost is close to lead-acid batteries.
Disadvantage: The energy density improvement is limited and still belongs to transitional technology.