Nowadays, new energy vehicle batteries are basically ternary hammer batteries or iron phosphate hammer batteries.The latter generally has a longer life span.However, both of these can be called "hammer batteries", and the following are commonly referred to as hammer batteries.
There are two main influencing factors in measuring the battery life of new energy vehicles: the number of charging cycles, and the time.In addition, there are several secondary influencing factors: the average power of charge and discharge, the battery storage and operating ambient temperature, and the depth of charge and discharge.
1. The number of charging cycles.Usually under ideal conditions, the number of charging cycles can be about 1000-2000 times, and more than 70% of the available capacity can be guaranteed.If it is a PHEV, the mileage of a single cycle is generally about 50-80 kilometers, so before the battery is scrapped, it can be used for about 100,000 kilometers of pure electricity.But because PHEVS tend to have a lot of mileage in hybrid Q, they can probably be charged according to the number of times.In any case, the battery capacity of the PHEV is small, so the service life is also short.In theory, the usable life of a PHEV private car is about 5-10 years.
However, the BEV of a pure electric vehicle is easier to calculate.Taking the mainstream 400-kilometer battery life model as an example, it can travel 400 kilometers on a single charge. According to at least 1,000 cycles, the theoretical usable life is 400,000 kilometers.If it is 100,000 kilometers per year (operating vehicles), the theoretical life span is 4 years.If it is 20,000 kilometers per year (private car), the theoretical life span is 20 years (really? ).But doesn't it mean that 0.5 million kilometers per year can be used for 80 years? This involves the next factor
2. Use time.Usually, the battery only needs to be properly maintained and there is no problem with 10 years of use.At least my Nokia 3120 mobile phone battery is only still powered.For a longer period of time, it is more difficult to say because of various maintenance problems and the decay of the active substances of the battery itself [1].Judging from actual use experience, it is no problem for the hammer battery to have a battery life of more than 10 years under appropriate storage conditions, but it is hard to say if it is more than 20 years.
3. The average power of charge and discharge.In short, fast charging affects battery life.How influential is it?smaller.But it does have an impact.According to various automotive news, if BEV accounts for 80% of the total situation with fast charging and 80% with slow charging, the former is slightly faster in terms of battery attenuation, but it is not obvious.People in the battery industry have also said that slow charging is good for battery life, but the impact of fast charging is actually not as obvious as imagined.During the normal life of the vehicle, the difference between the two is not very big.
Battery storage and operating temperature.Temperature also has a greater impact on the life of the battery.If the battery is operating below 0 degrees Celsius for a long time, or above 40 degrees, it will accelerate the aging and capacity attenuation of the battery, and this attenuation is irreversible [2].Fortunately, today's new energy vehicles are basically equipped with battery temperature control systems, which can enable the battery pack to work at a more suitable temperature.
5. Charge and discharge depth.Although the impact of this on battery life is a secondary factor, it may cause fatal damage to the battery in use.Many people subconsciously feel that the laptop battery is not durable and unused. It is the impression left by the laptop battery.Generally, after two or three years of use of notebook batteries, the capacity will be significantly reduced, and waste in the fourth year abound.In fact, this is not a battery pot, but our habit of using notebooks.Most people use notebooks that are connected to a power supply, which will keep the battery at 100% power for a long time.From a chemical point of view, this is a high-energy state, like a taut bowstring, which is unstable and fragile.The battery is in a high-energy state for a long time, which can easily lead to denaturation and inactivation of the active substance.Therefore, if you want to extend the life of the laptop battery, it is better to set the charging smell value 3] like Thinkpad (only if the battery power is lower than a certain set value, such as 70%, charging will start, so as to give the battery time to rest), and disconnect the power appropriately, and only use the battery for power supply.But this problem does not exist for new energy vehicles, because it is impossible for the car to be 100% powered all the time.So don't worry too much about this.
But what the car needs to worry about is the other extreme: the discharge depth%.Although the hammer battery has a long life, it can't help over-discharging, especially deep discharge.What is deep discharge? That means using less than 5% of the electricity, or even less than 0%.Deep discharge· is like starving a normal person for a day or two.Being hungry for a day or two will not die quickly, but doing so for a long time will have a great impact on health.And if the power is kept below 5% and the battery is not charged for a long time, the battery will be directly "starved to death", and there is no hope of "rebirth".If you put it for another half a month after deep discharge, don't worry, the battery life will be terminated immediately.