Evacuate the negative pressure. According to the personal research library, the principle of negative pressure formation heating of square batteries is mainly to use an air pump or hydraulic pump to suction the inside of the battery, thereby adjusting the internal air pressure of the battery. lithium battery, thus lowering the temperature. of the lithium battery, and reducing internal oxidation and reducing the reaction of the battery, thereby improving the safety of the battery.
Should the battery be kept warm in winter? Let's take a look at battery technology that can "self-heat".
Lithium batteries have a constant temperature in cold weather and a heating plate can be installed. According to the request for relevant information, if it is an existing battery, it is recommended to add a heating plate, although it will consume more energy, given that in dIn low temperature conditions, if there is no heating plate, it will release less. only 20% of the power, and when there is a heating plate, 50% of the electricity can be discharged.
Does the lithium battery have an impact on range in winter?
Is impulse self-heating really stable enough?
In fact, this is not the case. Although the whole design of this "pulse self-heating" technology has the potential of "black technology", in fact, this technology still needs running-in, debugging and optimization. Additionally, Changan Technology is not the first manufacturer in the market to use pulse self-heating technology for battery thermal management. BYD, which is both a battery supplier and an automobile brand, has actually applied this technology to its models.
This technology is mainly used ins BYD's DM-i super hybrid model. BYD's hybrid specific blade battery uses a pulse self-heating thermal management system. However, BYD's technology is somewhat different from the solution used by Changan Deep Blue. Changan Deep Blue uses alternating current to heat the ternary lithium batteries, while BYD's solution uses two sets of lithium iron phosphate blade batteries to discharge each other (DC). for heating.
In principle, in fact, Changan and BYD use a solution that uses a method in which current passes through a large resistance to generate heat after the temperature drops and the internal resistance increases. However, Changan generates an alternation. current outside the battery for overcharging, while BYD uses two batteries to supply DC power to each other to "heat" each other. This is similare to the CATL solution.
BYD's current model using this technology is Qin PLUS. The current Qin PLUS DM-i will be launched in March 2021. After the launch, DM-i also appeared online. There are some issues in actual use. Among them, the most common answer from car owners is that Qin PLUS DM-i will experience engine shaking and misfire in low temperature environments.
This situation is linked to the pulsed self-heating technology used in the blade battery. The manufacturer's temperature setting for the self-heating function is too extreme, causing the pulse self-heating function cannot start normally at non-extremely low temperatures, and the DM-i engine requires a battery to run it. The motor gives the motor an initial speed so that the motor can avoid shaking when starting.
Therefore, theThe situation encountered by Qin PLUS DM-i owners above is caused by the failure of the pulse self-heating function which does not work properly at non-extremely low temperatures. At the same time, since the pulse self-heating function requires two batteries to charge and heat each other through a voltage boost schedule, when using the pulse self-heating function pulse, the battery cannot produce a full and continuous operating voltage, and therefore cannot normally provide stable power for the electric drive, which also shows that the DM-i model can only choose between the Pulsed self-heating and electric drive.
After seeing the problems caused by BYD technology, we as consumers should still be cautious about Changan's technology. Changan must resolve otherproblems as electric propulsion/self-heating. In addition to choosing one of the two, additional efforts are required for the identification of the ambient temperature and the calibration of the start of self-heating. We also look forward to Changan providing the actual measured data of “microcore high-frequency pulse self-heating” technology.
Summary:
In an era where traditional brands and new power brands clash, the arms race is not only about In terms of mechanical adjustment, but also in terms of high-precision technology, this is a key link, so it is not difficult to understand why Changan has worked tirelessly to launch a new electric platform. Judging from the pulse self-heating technology announced this time, technical improvements are worth looking forward tos, but technology ultimately depends on experience. In addition, the last car manufacturer using pulse self-heating technology suffered heavy losses in low temperature areas. , this time Changan launches another model with this technology, and we hope Changan can give our consumers a satisfactory answer in terms of fit and actual testing experience. (Text: Gao Zijian)
Expand the rest of the text (1/2) 2 Back to top Is impulse self-heating really stable enough?In fact, this is not the case. Although the whole design of this "pulse self-heating" technology has the potential of "black technology", in fact, this technology still needs running-in, debugging and optimization. In addition, Changan Technology is not the first manufacturer in the market to use pulse self-heating technology for heat management.battery power. BYD, which is both a battery supplier and an automobile brand, has actually applied this technology to its models.
This technology is mainly used in BYD's DM-i super hybrid model. BYD's hybrid specific blade battery uses a pulse self-heating thermal management system. However, BYD's technology is somewhat different from the solution used by Changan Deep Blue. Changan Deep Blue uses alternating current to heat the ternary lithium batteries, while BYD's solution uses two sets of lithium iron phosphate blade batteries to discharge each other (DC). for heating.
In principle, in fact, both Changan and BYD use a solution in which current passes through a large resistance to generate heat after the temperature drops and the internal resistance increases. However, Changan generates a calternating current outside the battery for overcharging, while BYD uses two batteries. packs to provide direct current to each other. “Heating” is similar to CATL’s solution.
BYD's current model using this technology is Qin PLUS. The current Qin PLUS DM-i will be launched in March 2021. After the launch, DM-i also appeared online. There are some issues in actual use. Among them, the most common answer from car owners is that Qin PLUS DM-i will experience engine shaking and misfire in low temperature environments.
This situation is linked to the pulsed self-heating technology used in the blade battery. The manufacturer sets the temperature setting for the self-heating function too extreme, which prevents the pulse self-heating function from starting normally at non-extremely low temperatures. EngineDM-i requires a battery to drive the motor. The motor has an initial speed so that the motor can avoid start-up time jitter.
Therefore, the situation encountered by Qin PLUS DM-i owners above is caused by the failure of the pulse self-heating function which does not work properly at temperatures not extremely low. At the same time, since the pulse self-heating function requires two batteries to charge and heat each other through a voltage boost schedule, when using the pulse self-heating function pulse, the battery cannot produce a full and continuous operating voltage, and therefore cannot normally provide stable power for the electric drive, which also shows that the DM-i model can only choose between the Pulsed self-heating and electric drive.
After havingConsidering the problems caused by BYD technology, we as consumers should always be cautious about Changan's technology. Changan needs to solve other problems besides electric propulsion/self-heating. In addition to choosing one of the two, additional efforts are required for the identification of the ambient temperature and the calibration of the start of self-heating. We also look forward to Changan providing the actual measured data of “microcore high-frequency pulse self-heating” technology.
Summary:
In an era where traditional brands and new power brands clash, the arms race is not only about level of mechanical adjustment, but also at the level of high precision technology, this is a key link, so it is not difficult to understand why Changan has worked tirelessly for thelaunch a new electrical platform. Judging from the pulse self-heating technology announced this time, technical improvements are worth looking forward to, but technology ultimately depends on experience. In addition, the last car manufacturer using pulse self-heating technology suffered heavy losses in low temperature areas. , this time Changan launches another model with this technology, and we hope Changan can give our consumers a satisfactory answer in terms of fit and actual testing experience. (Text: Gao Zijian)
@2019Lithium batteries impact cruising range in cold winter.
The working principle of a lithium-ion battery is that the internal electrolyte changes through chemical reactions, causing a potential difference between the positive and negative electrodes to generate current. In an environment withlow temperature, the electrolyte moves very slowly, which affects the transfer activity of lithium ions between the positive and negative electrodes, resulting in a decrease in the charging and discharging performance of the battery.
To put it simply, in a low temperature environment, it is not that the lithium battery is really discharged, but that it is powered but cannot be released normally. According to analytical data, the capacity of ordinary lithium batteries will be reduced by 20% at zero degrees Celsius, and when it reaches minus 10 degrees Celsius, the capacity may only be about half.
Detailed information:
Precautions for winter use:
1. Find a warm place to charge
When charging an electric vehicle when the ambient temperature is below 0℃, the system automatically heats the cellsfrom the battery first when the battery cell temperature exceeds 5℃. , only then will you actually start charging the vehicle. Some electric vehicle owners may feel that the charging speed of electric vehicles suddenly slows down in winter. This actually means that there is additional time to heat the battery cells before recharging the vehicle.
Therefore, when car owners usually charge their cars, they should try to do so in underground parking lots, closed garages and other places. This will help improve battery activity, not only reducing loss of cruising range, but also improving charging efficiency and saving time.
2. Charge for a short time before traveling
The electric car still had 60% or 70% of its power on Fridayille, but when I started the car the next morning, I discovered that only 60 or 70% of the power remained, or even less. Some call this situation a “power outage.” In fact, this “power outage” is not a fault, but is caused by low temperature. When an electric vehicle is driving, the battery is in a continuous discharge state, the temperature will be relatively high, and the battery voltage will also be relatively high. The remaining power of the electric vehicle displayed at this time is a normal value.
However, after being parked at low temperatures overnight, the battery cooled and the voltage dropped. At that time, the car's system will automatically adjust the displayed power and cruising range, which creates a ". The illusion of "running out of power". In this case, you usually just need to get out in advance and charge the battery for approximately 10 minutes
3. Drive steadily and not in a hurry
When driving an electric vehicle, you should start slowly and avoid violent driving such as sudden deceleration, sharp turns and sudden braking. Good driving habits can effectively reduce the speed of battery consumption. The time between starting the car should not exceed 5 seconds, and the interval between restarts should not be less than 15 seconds.
If the battery mileage decreases too much, go to the 4S store to check the car battery in time, replenish the battery electrolyte in time, and adjust the electrolyte proportion.
People's Daily Online - Mobile phone automatically turns off when frozen? Lithium battery products undergo extreme cold test
People's Daily Online - Electric vehicles in winterBattery rangeie is reduced? How to "survive the winter"