Research on new energy vehicles use lithium battery heating effect

Source: 2020 - 04 - 10 19:03 hits: time is the power of the new energy vehicles by a single li-ion battery series parallel combination methods such as huge lithium battery, the battery has a higher requirement of large current charge and discharge, especially the normal working condition of the car, in the face of all kinds of working conditions, lithium battery discharge sharply in a short time, usually need for fast charging and battery, this will lead to the working state of the battery produces a lot of heat. Heat must be send out in time. If not timely dissipation, the temperature of the battery will be rise in the agreed upon period of time, affect the normal work of the battery, or even cause safety accidents. At the same time, if the battery for a long time in the working state, can seriously reduce the service life of batteries. With a single lithium-ion battery as the research object, this paper systematically studied the thermal effect under the condition of the lithium-ion batteries in charging and discharging of heat insulation, thermal insulation and natural cooling, which laid a foundation for the application of lithium battery of new energy vehicles. The heat effect of lithium ion battery is composed of two compounds, they can be reversibly embedded lithium ion, can also be embedded lithium ion. Battery charging and discharging by lithium ion movement between the positive and negative. At present, lithium ion battery anode materials mainly adopts L iCo O2. When charging, the voltage between the poles to force the anode of lithium ion release lithium ion, lithium ion embedded in lithium carbon compounds with lamellar structure arrangement. In the process of discharge, lithium lithium ion from the cathode layer of carbon compounds separated, and combined with the anode layer compound to. An electrical current lithium ion movement. Battery heat of reaction: lithium iron phosphate battery of the electrochemical reaction 2 as follows. Ion battery heating model of lithium ion battery can be divided into cylindrical and square, and polymer lithium ion can be made into any shape. The research object of this article is square lithium ion battery. According to the basic principle of lithium ion battery thermal effect, set up the heating effect of the lithium ion battery under rectangular coordinate system mathematical model, the basic state and thermal effect of lithium ion battery has carried on the mathematical description. The establishment of the mathematical model is usually under ideal conditions, lithium battery, the mathematical model of heat effect is not exceptional also, this requests us to necessary to simplify the battery. Simplified as follows: (the specific 1) Because we analyses the liquid lithium ion battery, the electrolyte flow hardly, so you can ignore the convection effect of electrolyte. ( 2) Lithium battery in the working process of the radiant heat effect is very small, can be neglected. ( 3) Because the mathematical model was established under ideal conditions, so assume that the parameters of the battery remains the same, ignore the influence of temperature to the battery. ( 4) Battery cathode, anode materials and electrolyte materials are the same. ( 5) Heat uniform distribution in the battery. ( 6) Lithium battery in each direction coefficient of thermal conductivity is the same. Ion battery during charging and discharging, polarization reaction will happen, in this case the average voltage and open circuit voltage deviation can be generated due to the polarization heat, the heat generated by the voltage deviation is called polarization hot in lithium ion battery charging and discharging are positive. Lithium ion battery electrodes, self-discharge phenomenon leads to the electrode decomposition. The heat generated by the discharge electrode itself is called heat decomposition. The heat is small, the charge and discharge can be neglected. Lithium-ion batteries in charging and discharging process of heat is called a joule heat, this part of the heat is positive. Usually, the lithium ion battery discharge is far greater than when the heat generated by the lithium ion battery charge generated under high temperature, according to the situation, this paper discusses the battery in the process of charging and discharging the heat generated by the, according to the heat generated by the cooling measures, therefore, battery charging and discharging protection.