[0023] In order to make the technical means, creative features, objectives and effects of the present invention easy to understand, the present invention will be further described with reference to specific embodiments.
[0024] First of all, the current mainstream research direction of high-temperature lithium batteries is to find new electrolytes, such as molten salt electrolytes that can be liquid at lower temperatures, and molten salt electrolytes with higher conductivity. However, changing the shape of the battery shell of the high-temperature lithium battery has been neglected. Changing the shape of the battery shell of the high-temperature lithium battery can also improve the performance of the high-temperature lithium battery.
[0025] Secondly, by changing the shape of the high-temperature lithium battery, the performance of the high-temperature lithium battery can be improved to a certain extent in a relatively quick way, so that it can work better.
[0026] The current high-temperature lithium battery has a relatively simple shape and may not be able to meet the requirements and tests of various environments. Therefore, it can be seen from the other hand that it is quite necessary to change the shape of the high-temperature lithium battery. Through the present invention, from another perspective, a possible condition and method are provided for improving the use of high-temperature lithium batteries, which is also the central content of this research.
[0027] As we all know, there are three ways to transfer heat: heat conduction, convection and heat radiation. In the actual process, several ways are often carried out simultaneously.
[0028] Heat conduction: When the temperature in the thermodynamic system is uneven, heat is transferred from a higher temperature to a lower temperature. The main form of heat conduction solid heat transfer, the heat conduction properties of various substances are different. Generally, metals are hot. Good conductor. Glass, wood, cotton and wool products, feathers, fur, as well as liquids and gases are all poor conductors of heat.
[0029] Convection: The process of making the temperature zone uniform by circulating the fluid between the hot part and the cold part of the fluid (gas or liquid). Convection is usually the main way of heat transfer in a fluid (gas or liquid), and the convection line of gas is more obvious than that of liquid. Convection can be divided into natural convection and forced convection. Convection that occurs naturally due to uneven temperature is called natural convection. Due to external influences, such as fluid agitation, convection is called forced convection.
[0030] In gas or liquid, the process of heat conduction and convection often occur simultaneously.
[0031] The present invention provides a method for testing the influence of the shape of a lithium battery on the thermal conductivity of the lithium battery. The steps of the invention are as follows:
[0032] Pour the same quality aluminum hydroxide powder as the inner core of the simulated battery into four cylindrical containers and put them aside for later use. The four cylindrical containers are a cube container, a rectangular parallelepiped container, a cylindrical container, and an ellipsoidal container.
[0033] Put the dry yellow sand into a stainless steel circular box, then put it on a gas stove to heat it, turning it over while heating, so that the upper and lower temperatures are more uniform. When the surface temperature of the yellow sand reaches 120℃, use a smaller flame to keep the surface temperature of the yellow sand no longer changing (after changing a cylinder, repeat it once to ensure that the experiment is always in the same temperature environment get on).
[0034] When the container is buried in the hot yellow sand, (make the yellow sand and the aluminum hydroxide powder in the container on a plane), quickly insert the DIS temperature sensor in the center of the powder (that is, the geometric center of the container) (2cm from the upper surface of the powder, Note: The powder is 4cm deep).
[0035] Such as figure 1 , figure 2 with image 3 As shown, when the measured temperature reaches about 20°C, the recording starts. Due to the limited time interval of the DIS temperature measurement software, each record is divided into three times (the temperature sensor is not taken out). The DIS temperature sensor records the values of the four cylinder DIS temperature sensors between 0 and 120 seconds; the DIS temperature The sensor records the values of the four cylinder DIS temperature sensors during 120-240 seconds; the DIS temperature sensor records the values of the four cylinder DIS temperature sensors during 240-360 seconds; each time is 120 seconds, a total of 360 seconds.
[0036] Since each recording interval (storage temperature-time curve) takes less time (about 2.5 seconds), the whole process is 5 seconds, and for different samples, the time is almost equal, so this point will not be mentioned in the following experimental analysis.
[0037] After the above operation is over, based on the data (curve image) stored in the computer, analyze again and draw a preliminary conclusion.
[0038] The present invention hopes to shorten the time for the solid electrolyte used in high-temperature lithium batteries to transform into a molten state on the existing basis in practical applications. In this process, since it is a solid electrolyte, heat conduction is the main heat transfer method. In the experiment Attention will be paid to make the heat transfer method in the experiment as heat conduction as possible.
[0039] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the industry should understand that the present invention is not limited by the above-mentioned embodiments. The above-mentioned embodiments and the specification describe only the principles of the present invention. The present invention may have various forms without departing from the spirit and scope of the present invention. Changes and improvements, these changes and improvements fall within the scope of the claimed invention. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.
