What are the differences between lithium iron phosphate battery packs and lead-acid batteries?
For the same volume, the energy density of lithium iron phosphate batteries is 3 to 4 times that of lead-acid batteries, 2.5 times that of nickel-cadmium batteries, and 1.8 times that of nickel-metal hydride batteries. Therefore, with the same battery capacity, lithium-ion batteries are smaller and lighter than lead-acid, nickel-cadmium, and nickel-metal hydride batteries.
1. Lifespan: Lead-acid batteries have a cycle life of around 300 cycles. Lithium iron phosphate battery packs, at room temperature and 1C charge/discharge, retain more than 80% capacity after 2000 cycles per cell, and their 3C cycle life exceeds 800 cycles. Lead-acid batteries are highly sensitive to environmental temperature; under harsh conditions, their lifespan does not exceed 5 years. Lithium iron phosphate batteries, under the same conditions, have a much longer lifespan.
2. Safety Performance: Lead-acid batteries can explode under strong impact, posing a threat to consumer safety. Lithium iron phosphate battery packs: Lithium iron phosphate batteries completely solve the safety hazards of lithium cobalt oxide and lithium manganese oxide. Lithium cobalt oxide and lithium manganese oxide can explode under strong impact, while lithium iron phosphate has undergone rigorous safety testing and will not explode even in severe collisions.
3. Temperature range: Lead-acid batteries can be used in a temperature range of -20℃ to 50℃ and have low self-discharge. Lithium iron phosphate battery packs have a peak thermal temperature of 350~500℃ and a wide operating temperature range (-20~+75℃), and can still discharge 100% even at high temperatures (60℃).
4. Charging efficiency: For lead-acid batteries, the charging time for a typical electric vehicle lead-acid battery charger is about 8-10 hours when the battery is 100% depleted. Due to the higher activity of lithium battery materials and electrolytes, lithium iron phosphate battery packs can be charged quickly, allowing for high-current 2C fast charging and discharging. With a dedicated charger, the battery can be fully charged in 40 minutes at 1.5C, and the starting current can reach 2C.
5. Regarding the absence of memory effect: Lead-acid batteries exhibit a memory effect; rechargeable batteries often operate under conditions where they are not fully discharged, causing their capacity to rapidly drop below their rated value. Lithium iron phosphate battery packs do not exhibit this phenomenon; the batteries can be charged and used immediately regardless of their state, without needing to be fully discharged before recharging.
6. Environmental friendliness: Lead-acid batteries in electric vehicles contain large amounts of lead, which can pollute the environment if not properly disposed of after disposal. Lithium iron phosphate batteries, on the other hand, contain no heavy or rare metals, are non-toxic, and cause no pollution during production or use. They comply with European RoHS regulations and are considered green and environmentally friendly batteries, making them a hot topic of research and attention.
In terms of price, the mainstream batteries on the market are currently 48 volts. If you want to replace them, lead-acid batteries cost around 380-450 yuan (48V12AH-48V20AH) with a warranty period of 1 year. Lithium-ion batteries are relatively more expensive, costing around 1000 yuan (48V12AH), but their warranty period is 2 years.
Currently, lithium iron phosphate battery packs are about three times more expensive than lead-acid batteries. However, considering the lifespan, lithium-ion batteries still have a longer lifespan for the same investment.
Lead-acid batteries hold the largest market share and are the most widely used type of chemical battery, especially in applications such as starting and large-scale energy storage, where they are unlikely to be replaced by other new types of batteries for a considerable period. Lead-acid batteries are relatively inexpensive and possess comparative advantages such as mature technology, excellent high and low temperature performance, stability and reliability, high safety, and good resource reusability, giving them a clear competitive edge in the market.
