Electric vehicle battery safety issues need attention

As the temperature rises gradually, more and more people start to use electric cars in the street, and the battery safety of electric cars also attracts more and more attention from consumers.

According to the types of batteries, the current electric vehicles on the market are mainly divided into lead-acid battery models and lithium battery models. Regardless of the type of battery model, from the purchase to the use of the process should pay attention to safe operation.

Lead acid and lithium power battery technology and the maturity of the two performance difference is bigger, lead-acid battery technology has a history of hundreds of years, due to its characteristics of high stability and lead element is widely used, and lithium ion battery had been in more than 30 years of the development of the technology is relatively mature, but as a result of lithium lively performance, application range is relatively small. The performance differences between the two types of batteries are mainly in the following aspects:

1. Environmental protection. Lithium battery has no pollution (not absolutely), while lead-acid battery has heavy metal pollution due to improper recycling

2. Specific energy. The mass to volume ratio of lithium batteries is about 40% higher than that of lead-acid batteries.

3. Price. Lithium-ion batteries cost more than twice as much as lead-acid ones

4. Service life. Currently, the common lithium iron phosphate has no memory effect after being charged for 1,500 times. After being charged for 1,500 times, it has about 85% storage capacity, while the lead-acid battery has about 500 times and has obvious memory effect

5. Self-discharge rate. The monthly self-discharge of lithium battery is less than 3%, and that of lead-acid battery is 15% to 30%.

6. Discharge characteristics. Simply put, the same capacity of the battery, large current discharge, lithium batteries than lead-acid batteries give out about 30% more electricity.

7. Voltage platform. Lithium battery voltage platform is greater than 3V, lead-acid battery is 2V

In this special note, two types of battery safety performance. The safety of dynamic lithium batteries (lithium manganese acid, lithium iron phosphate) varies with different materials. Lead-acid battery technology has been quite mature, and the overall safety is higher than lithium batteries.

Jerry-built wiring is bad for batteries

Since lead-acid batteries are safer than lithium ones, is it true that lithium electric cars are more likely to explode than lead-acid electric cars? Not really.

Electric vehicle battery safety problems often occur in the charging process of electric vehicles, which has little to do with the performance of the battery itself.

Electric vehicle charging the battery itself is not likely to happen when the short circuit, and seldom explosion or burning, electric car batteries and chargers are generally provided with protection, control of lithium battery and protection circuit board, once too strong or short circuit, electricity protection system will automatically cut off, to prevent electric vehicles due to short circuit or fire and explosion.

Lead acid battery fire causes generally and connection line aging, or manufacturers cut corners line heat poor, and lithium tram explosion or fire, in addition to line aging or heat resistance problems, but also may be the battery internal protection system failure.

In addition, if consumers in the process of using improper operation, battery damage, charging time is too long and other reasons, will also increase the risk of short circuit battery.

Loose connection is easy to cause accidents when riding

The electric vehicle should bear strong vibration when running, and the reliability of all connections should be evaluated. The connector should have the function of "self-locking" to prevent it from falling off during vibration and pulling. The connection of the battery connector with the electric vehicle should adopt the connector, and be firmly welded with solder. If the contact is not firm and the degree is relatively light, poor conductivity will occur, making the contact part of the circuit hot, the circuit loss is large, and the output voltage is low, which will affect the motor power and reduce the driving range or make it unable to ride normally.

In driving process or in the process of charging contact not firm, may produce circuit, open circuit generates a strong spark and possible deployment of electric vehicle battery internal explosive gases, especially those who just charged electric motor car battery, because the battery can be the detonation gas, and electric vehicle battery, circuit when the spark is strong, the possibility of explosion is considerable.

Lithium battery can not be charged but put to ensure good condition

Both lead-acid batteries and lithium batteries should try to prevent charging time is too long, a charge time should not exceed 8 hours, and try not to have violent collisions or contact with hot objects. Lithium-ion batteries, in particular, take too long to charge or wait until the battery is completely used up before recharging.

Since lithium batteries have no memory effect, the amount of each charge does not affect the battery's energy storage effect. On the other hand, if a charge time is too long, it will affect the consistency of the battery pack, thus affecting the life. And this loss of life is not recoverable, so special care should be taken not to charge too full at one time, it is recommended that 80% is the best.

Discharge situation is the same, when charging the battery to have a little electricity, electric vehicles do not run a little electricity is not recharged, that also affects the battery life.

In addition, after the battery is completely discharged, consumers should try to make up the battery immediately to avoid charging in the low temperature environment. If the electric bicycle is not used for a long time, it is necessary to remember to make up the battery timely. This can not only prolong the life of the battery, but also ensure the stability of the battery performance.

Electric vehicle security from the beginning of the purchase

Thus, to ensure the safety of electric vehicles in the process of use, consumers have to start to pay attention to the purchase. Current, the protection system of normal manufacturer is more perfect, circuit material and each component interface are more normal. Consumers do not covet cheap, must choose regular manufacturers or well-known brand electric models.

In addition, in the process of use, consumers should also pay attention to the standard operation of electric vehicles and batteries to prevent over-charging and over-discharge. After the electric vehicle battery is heated, cooling measures should be taken. Charging can only be carried out when the battery temperature of the electric vehicle returns to normal. The electric vehicle battery should be installed in a position to ensure good heat dissipation as far as possible. If it is found to be overheated, the charging should be stopped. The charger and electric vehicle battery should be checked. The charging time should be shortened when the electric vehicle battery discharging depth is shallow or the ambient temperature is high. Electric vehicle battery discharge to the termination voltage, continue to discharge called over discharge. Over discharge will seriously damage electric vehicle battery, electric vehicle battery electrical performance and cycle life is very adverse.

In general, consumers should not judge the quality of a car only by the price, range and other factors when choosing an electric car. It is equally important whether the contact between line materials and parts is good or not. And the battery must not have short circuit, should be especially careful about the installation or use, tools used in insulation measures should be taken, attachment should be outside of the battery electric even better, through inspection without short circuit, and finally even on electric vehicle batteries, wiring specification should be good insulation, prevent overlapping compression fracture, only in this way can make electric cars safer, use longer.

The page contains the contents of the machine translation.