RV parking air conditioners often have two considerations when choosing energy storage batteries: low-cost lead-acid batteries are too bulky, and high-cost lithium iron phosphate batteries are too expensive; whether to choose a battery that does not take up much space in the car or choose energy density What about higher ferroelectrics? This problem is not true. It is unwise to choose lead-acid batteries as energy storage batteries for RVs, bed carts or trucks, and the problem is not the size, but the cost of later use.
Advantages and disadvantages of lead-acid batteries
Both the starter battery of the car and the power battery of the battery car are lead-acid (including maintenance-free). The negative electrode of these batteries is lead, the positive electrode is lead dioxide, and the electrolyte is a sulfuric acid solution. The main material determines that the durability must be poor because lead sulfate will be produced during operation, which will gradually sulfide the electrode plate and affect the charging and discharging efficiency; the electrolyte will slowly evaporate during use, and no matter how it is adjusted in the later stage ( Adding water) is difficult to balance to the best condition.
Lead-acid batteries can also be used as starting batteries, because most car users will not stay in the car for a long time after the flame is turned off, and the vehicle's quiescent current and the anti-theft system sensors will not consume excessively and quickly. But it is not durable when used as a power battery or chemical power source. For example, a two-wheeled battery car basically needs to replace a set of batteries a year, otherwise, the cruising range may be reduced by half. In other words, the actual service life of a lead-acid battery is only about 350 times (full charge and discharge), so is it suitable as a parking air conditioner power supply?
A lead-acid battery pack with a capacity of 1kwh also costs 700 to 800 RMB, and parking air conditioners often require 2~3kwh of energy storage. The use of lead-acid batteries requires an investment of about 2K. If the parking air conditioner is used frequently, the battery pack needs to be replaced in 1 to 2 years. Is this cost higher or lower than lithium iron phosphate batteries?
Advantages and disadvantages of lithium iron phosphate batteries
The advantages of iron batteries are firstly safety and environmental protection. The metal materials used in their manufacture are not heavy metals like lead, and the electrolyte is almost zero pollution. The thermal runaway temperature of this kind of battery in operation is very high (hundreds of degrees Celsius), and it is still the most ideal new energy vehicle option for use as a power battery; and a special mechanism can withstand impact and puncture to ensure no fire, compared with lead Acid batteries are more reassuring as storage batteries.
The second advantage of iron batteries is their small size, low weight, and high energy density. The capacity of a lithium iron phosphate battery pack with the same weight will be 3 to 4 times that of a lead-acid battery. Therefore, it will not occupy too much space in the car, and will not increase fuel consumption due to the increase in weight. These two points are also the absolute advantages of iron batteries. However, the advantages that play a decisive lead are not the above points: the complete charge and discharge can be used about 2000 times, and the SOC still has a margin of 60% to 70% is the absolute advantage.
The service life of lithium iron phosphate batteries is far beyond the reach of lead-acid batteries. Although its cost is 1,000 to 1,300 RMB per kilowatt, it is still more economical for long-term car use. Therefore, for cost control, safety protection, and space utilization, it is recommended to choose iron battery packs for parking air conditioners; charging needs to use the original car battery to connect to the inverter with a 4/6 square wire lead, and the battery pack should also be added to the inverter. Use 220V voltage for charging. Batteries with different parameters cannot be charged in parallel, even if they are both lead-acid batteries, it will accelerate the damage of the battery.
