How to solve the low temperature performance anxiety of power battery in winter?

2020-12-14 18:28:01 0

Every winter, especially in the northern winter, the poor low-temperature performance of electric vehicle power battery will become the worry of the owners, and some riders jokingly claim that they have bought an "electric dad".

In the cold winter season, in order to start the electric vehicle, it is necessary to heat the battery to normal state, low-temperature heating, heating with warm air, seat heating and power app opening Every operation consumes power. According to industry insiders, originally, private electric vehicles may be charged at 60 degrees, but various "necessary" functions such as low-temperature battery heating and heating may take away more than ten degrees of electricity. It is not surprising why electric vehicles become so popular in the cold winter.

In addition, due to the low external temperature in winter, some types of batteries also face more problems such as power attenuation at low temperature during the operation of vehicles, and the more serious situation may be the direct "strike" of vehicles. According to industry insiders, in some northern cities, bus batteries are often frozen after a night of heavy snow, which requires staff to carry out maintenance before normal charging.

Obviously, in winter, poor low-temperature performance of electric vehicle power battery is still a major concern for consumers to use and purchase electric vehicles.

According to the analysis of industry insiders, there are many reasons for the poor low-temperature performance of the power battery of electric vehicles in winter. For example, the battery needs to be heated before the vehicle starts to make its temperature rise to the normal state. This power source comes from the battery pack itself. At the same time, the opening and use of various application functions such as air conditioning and seat heating in the car in winter will use electricity, resulting in a rapid decline in electricity.

For public transport vehicles, the winter challenge is even greater. Due to the fact that the power of general power battery decreases faster at low temperature, it needs frequent charging, which makes the operating cost increase in disguised form. In addition to the decline of battery power, there is also a pain point is the lower temperature in winter, charging also becomes more difficult. There are bus drivers Tucao, in the north of winter, make complaints about slow charging, slow charging and super slow charging.

According to battery, for the pain point of battery power attenuation in winter, battery enterprises and automobile enterprises are striving to solve this pain point. For example, some battery enterprises in China have developed the "cell self heating technology". By using BMS control algorithm and vehicle powertrain architecture, the battery cell can be quickly charged and discharged in a short period of time, so that the battery core can be heated from the inside, and the self heating effect of the cell can be realized.

Of course, not all batteries have pain points of decay and slow charging in extreme cold or winter. At present, silver titanate lithium battery has obvious advantages in temperature resistance and wide performance, and the power attenuation can be almost ignored in extremely cold conditions. According to industry insiders, lithium titanate has a stable structure, and its spinel structure has a three-dimensional lithium ion diffusion channel, and its dynamic properties can still maintain the state at normal temperature at low temperature, "the normal charge and discharge can be achieved from - 50 ℃ to 60 ℃ above zero, so as to ensure the normal operation of vehicles at low temperature."

In fact, because of its good wide temperature resistance, lithium titanate battery can be charged and discharged normally in extremely cold and plateau areas without attenuation. At present, many areas in the north take the silver dragon lithium titanate battery as the first choice when promoting bus to electric switching. According to battery, at present, the new energy buses in Harbin, Jinzhou, Baotou and other northern cities mainly use lithium titanate battery technology route, and the buses mainly come from Yinlong new energy.

In 2017, Yinlong pure electric bus equipped with lithium titanate power battery was officially put into operation in Harbin. Harbin has a large seasonal temperature difference, which will reach above 30 ℃ in summer and drop to - 30 ℃ in winter, "but Yinlong car has withstood the test and has not had any problems in three winters. Yinlong pure electric vehicle, battery performance is very good. " Harbin Futong bus passenger transport Co., Ltd. bus driver stationmaster said.

"Buses with conventional batteries have to be heated before they can start charging. It's very troublesome and often affects the normal driving time in the morning. " Zhai Shifu, a driver of Futong passenger transport, said, "Yinlong bus is much simpler. Lithium titanate battery has better activity. We don't need to deal with normal charging and discharging. It's much more convenient than buses with traditional batteries."

It is worth mentioning that lithium titanate battery also plays an important role in the public transport system in Beijing. In addition to the low temperature in winter in Beijing, the lithium titanate battery has almost no attenuation and normal charge and discharge at low temperature, and its excellent fast charging performance at low temperature is also an important reason why Beijing urban public transport system favors it.

Recently, according to CCTV finance and economics channel, "lithium titanate battery has a wide range of applicable temperature. In the laboratory, the reporter saw that the minimum temperature of the simulation experiment is - 50 ℃, and the maximum temperature is 60 ℃..." "The bus equipped with Yinlong new energy lithium titanate battery can be fully charged in only 8 minutes." Urban bus passenger transport and scenic spot vehicles are all operational vehicles, which require high charging efficiency. However, silver titanate lithium battery has good fast charging performance and can be normally charged and discharged at low temperature. There is no pain point of "fast charging to slow charging" of other batteries at low temperature. This should also be the lithium titanate battery in more and more fields, especially urban bus The reasons for the increasing trend of the proportion of medium