Recently, electric vehicle fires have occurred in many places in China. At about 17:00 on February 25, @Beijing Fengtai Fire issued a notice: At 10:13 on February 25, 2024, the 119 command center received a call from Xurijiayuan, Majiabao Street, Fengtai District. When an alarm broke out about a fire in the electric carport on the north side of Building No. 10 in Community B, nearby fire rescue forces were quickly dispatched to the scene. The open fire was put out at 10:26. After verification, the fire occurred on an electric bicycle in an outdoor independent electric car shed. The fire area was 10 square meters, and no casualties were caused. The cause of the fire was initially determined to be a battery failure. The Fengtai District Fire Rescue Detachment reminds the general public not to park or charge electric vehicles in public foyers, evacuation walkways, stairwells, safety exits, etc. Electric vehicles and batteries are not allowed to enter the building or home. The general public is requested to remind each other, standardize operations, and park safely to prevent accidents.

On February 23, a fire broke out in Building 6 of Mingshang Xiyuan in Yuhuatai District, Nanjing, killing 15 people and injuring 44 others. It was initially determined that the fire was caused by a fire where electric vehicles were parked on the elevated floor. Community resident Ma Lin@half-poor little pole posted twice in 2020 and 2021 to publicly appeal to the property management and the community, saying that a large number of electric vehicles were piled up in the elevator room, and the owners pushed electric vehicles into the elevator. There was a great fire hazard and he had too many electric vehicles. The feedback was fruitless.

The reasons why electric vehicles catch fire are as follows:

1. Problems with charging cables and chargers: The charging cables and chargers used may not meet standards, have low power, damaged circuit skins, short circuits between positive and negative poles, etc., which may cause fires. In addition, some inferior chargers lack power-off protection function. After the battery is fully charged, they continue to charge without automatically cutting off the power, resulting in long charging time or even spontaneous combustion of the battery.

lithium iron phosphate battery

2. The power connection cable is damaged: The battery connection cable may be damaged due to aging, corrosion, looseness, etc., which may cause a fire.

3. The leakage protection switch is not installed: The leakage protection switch can automatically turn off the power when a large current occurs in the line to play a protective role. However, the safety of some electric vehicle protection panels is not up to standard. Once a short circuit or overcharging occurs, the electric vehicle may spontaneously ignite.

4. Irregular charging circuit: For the sake of convenience, some electric vehicle owners will choose to pull the wires privately or push the electric vehicle indoors for charging. This operation is not only easy to cause fires, but also blocks escape routes and causes disasters. In addition, some power strips have multiple jacks, and sometimes several chargers charge on one power strip, resulting in unstable voltage, overcharging of the battery, and possible spontaneous combustion.

Modified electric vehicles: Some shops will modify the electrical wiring in the vehicle without permission and replace the battery with a larger capacity, causing the wires to be overloaded or short-circuited, causing a fire.

Wait for other reasons.

So, if you use our "lithium iron phosphate battery", compared with ternary lithium battery, the internal chemical structure of lithium iron phosphate is more stable and safer, and it can still remain stable under high temperature or overcharge conditions, followed by The cycle life is longer, ternary lithium has a cycle life of 800-2000 times, and lithium iron phosphate can have a cycle life of 4000+ times.

lithium iron phosphate battery

Advantages of lithium iron phosphate batteries:

1. High safety. Improved safety performance: The P-0 bond in the lithium iron cobaltate crystal is stable and difficult to decompose. Even at high temperatures or overcharge, it will not cause structural collapse or generate strong oxidizing substances like lithium cobalt oxide, so it has good security. Some reports pointed out that in actual operation, a small number of samples were found to be burning during acupuncture or short-circuit experiments, but no explosion occurred. In overcharge experiments, high-voltage charging that greatly exceeded the self-discharge voltage was found to still have explosion phenomenon. Even so, its overcharge safety has been greatly improved compared to ordinary liquid electrolyte lithium cobalt oxide batteries.

2. Super long life. Improvement of lifespan Lithium iron phosphate battery refers to a lithium-ion battery using lithium iron phosphate as the cathode material. The cycle life of long-life lead-acid batteries is about 300 times, and the maximum is 50 times. The cycle life of lithium iron phosphate power batteries reaches more than 20 times. With standard charging (5 hours rate), it can reach 20 times, with the same quality. The lead-acid battery is "half a year for the new, half a year for the old, and another half a year for maintenance", which is only 1 to 1.5 years at most. When used under the same conditions, the theoretical life of lithium iron phosphate batteries will reach 7 to 8 years. All things considered , the performance-price ratio is theoretically more than 4 times that of lead-acid batteries. Large-current discharge can quickly charge and discharge at a high current of 2C. Under a special charger, the battery can be fully charged within 40 minutes at 1.5C, and the starting current can reach 2C. Lead-acid batteries do not have this performance.

3. High temperature resistance. Lithium iron phosphate has good high temperature performance. The electric heating peak can reach 350C-500℃, while lithium manganate and lithium cobalt oxide are only around 200℃. It has a wide operating temperature range (-20C-75C) and has high temperature resistance. The electric heating peak of lithium iron phosphate can reach 350°C-500°C, while lithium manganate and lithium cobalt oxide are only around 200°C.

4. Fast charging capability. Large-capacity n-rechargeable batteries often work under the condition that they are often fully charged and the capacity will quickly fall below the rated capacity value. This phenomenon is called the memory effect. Like nickel gas and nickel-cadmium batteries, there is memory, while lithium iron phosphate batteries do not. With this phenomenon, the battery can be charged and used no matter what state it is in. There is no need to discharge it first and then charge it.

5. Light weight. The volume of a lithium iron phosphate battery with the same specification and capacity is 2/3 that of a lead-acid battery, and its weight is 1/3 that of a lead-acid battery.

6. Environmental protection. Lithium iron phosphate batteries are generally considered to be free of any heavy metals and rare metals | Ni-MH batteries require rare metals), non-toxic (SGS certified), non-polluting, in line with European ROHS regulations, and an absolute green battery certificate, so lithium The reason why the battery is favored by the industry is mainly due to environmental protection considerations. Therefore, the battery has been included in the "863" national high-tech development plan during the "Tenth Five-Year Plan" period, becoming a key national support and encouragement development project.