Why do AGV batteries choose lithium iron phosphate cells more often?

Why do AGV batteries choose lithium iron phosphate cells more often?

Firstly, we must determine the usage environment of AGV batteries. Due to the complex working environment and many uncertain factors of AGV cars, which are even used in flammable and explosive chemical dust workshops or warehouses with high humidity, AGV needs to have the ability to operate continuously in these working environments. To prevent battery short circuits, fires, current overdischarging, charging overvoltage, high temperature, insufficient capacity and other problems, battery safety is the first factor we need to consider. To meet these conditions, we need to start from the chemical characteristics of the battery cells and the production process characteristics suitable for the battery pack, in order to determine which type of battery cell needs to be selected.

At present, the main types of battery cells on the market are lithium batteries and lead-acid batteries, while lithium iron phosphate, lithium manganese oxide, lithium cobalt oxide, and ternary lithium batteries are all branches of lithium-ion batteries. Below, we will compare the characteristics of lithium iron phosphate batteries, ternary lithium batteries, and lead-acid batteries:

Comparison between lithium iron phosphate batteries and ternary batteries:
1. Lithium iron phosphate batteries have good high temperature resistance.
The high temperature resistance of lithium iron phosphate AGV batteries is better, able to withstand high temperatures of 350 ° C~500 ° C, while lithium manganese oxide and lithium cobalt oxide batteries are usually only around 200 ° C, and the materials of modified ternary lithium batteries will generally decompose at 200 ° C.

2. Lithium iron phosphate AGV batteries have a long cycle life.
The cycle life of lead-acid batteries is generally around 300 times, with an upper limit of 500 times;
The theoretical capacity of ternary lithium batteries can reach 2000 cycles, but in practical applications, the capacity will decay to 60% after about 1000 cycles;
The actual lifespan of lithium iron phosphate AGV batteries is about 2000 times, with 95% capacity remaining at this time, and their conceptual cycle lifespan is even more than 3000 times.

2、 Compared with lead-acid batteries, lithium iron phosphate AGV batteries have many advantages:
1. Large capacity.
The single unit of lithium iron phosphate AGV battery can be made into 5Ah~1000 Ah (1 Ah=1000mAh), while the 2V single unit of lead-acid battery is usually 100Ah~150 Ah, with a small variation range.
2. Strong fast charging ability.
The starting current of lithium iron phosphate AGV battery can reach 2C, achieving high rate charging; The current requirement for lead-acid batteries is generally between 0.1C and 0.2C, which cannot achieve fast charging performance.
3. Lightweight. The volume of a lithium iron phosphate AGV battery with the same capacity is two-thirds of that of a lead-acid battery, and its weight is one-third of that of a lead-acid battery.
4. Environmental friendliness.
Lead acid batteries contain a large amount of heavy metal lead, which generates waste liquid, while lithium iron phosphate AGV batteries do not contain any heavy metals and are pollution-free in production and use.
5. High cost-effectiveness.

Although lead-acid batteries have lower purchase costs than lithium iron phosphate AGV batteries due to their cheaper materials, their economic efficiency in terms of service life and daily maintenance is lower than that of lithium iron phosphate batteries. The actual application results show that the cost-effectiveness of lithium iron phosphate batteries is more than four times that of lead-acid batteries.

From the above analysis, it can be seen that AGV batteries require continuous operation, even when in standby mode, they will still output low current. These continuous operating characteristics cause the product temperature to rise, which is a major test for the technical and chemical characteristics of the battery itself. Lithium iron phosphate batteries have thermal stability, stable chemical performance, long cycle life, environmental protection and energy saving, and high performance. These characteristics are significantly better than lead-acid batteries and ternary lithium batteries. Therefore, choosing lithium iron phosphate batteries as RGV batteries or AGV batteries has scientific and economic basis, especially in flammable working environments. We also need to enhance the explosion-proof performance of AGV batteries, such as adding explosion-proof shells.