CN207134412U - A kind of titanizing barrier film superhigh temperature lithium battery - Google Patents

Abstract

The utility model discloses a titanium diaphragm ultra-high temperature lithium battery, which comprises a casing, a positive electrode, a negative electrode, a diaphragm and an electrolyte arranged in the casing; the diaphragm is arranged between the positive electrode and the negative electrode; the electrolyte is filled in the casing ; The diaphragm is a titaniumized diaphragm, and the titaniumized diaphragm can be a titaniumized polyethylene diaphragm or a titaniumized polypropylene diaphragm. The lithium battery of the utility model adopts a titanium diaphragm, which can achieve a high temperature of 85°C and still have good discharge performance, and can be well applied to the manufacture and use of power batteries for new energy vehicles, and has a positive effect on promoting the development of new energy vehicles. important meaning.

Description

A titanium diaphragm ultra-high temperature lithium battery

technical field

The utility model relates to a lithium battery, in particular to a titanium diaphragm ultra-high temperature lithium battery.

Background technique

Lithium battery refers to a battery containing lithium (including metal lithium, lithium alloy, lithium ion, lithium polymer) in the electrochemical system. Lithium batteries can be roughly divided into two categories: lithium metal batteries and lithium ion batteries. Lithium metal batteries are generally non-rechargeable and contain lithium in a metallic state. Li-ion batteries do not contain metallic lithium and are rechargeable. The lithium battery mentioned in the present invention refers to a lithium ion battery.

As a green new energy source, lithium batteries have been widely used in various fields, but their high temperature resistance performance is poor, especially in high temperature environments above 45°C, making them suitable for wearable products, automotive lithium batteries and Applications in special fields such as aerospace and military are subject to many restrictions. For example: if the lithium batteries on new energy vehicles in southern China or Southeast Asia do not solve the problem of high temperature resistance of lithium batteries, new energy vehicles will not be able to travel long distances in summer. In addition, if new energy vehicles want to truly achieve the experience close to that of traditional gasoline vehicles, shortening the charging time, improving the mileage and the convenience of charging are unavoidable topics, and the conventional lithium batteries currently on the domestic market generally cannot be charged at 55°C. normal work.

Separator materials, as an important part of lithium-ion batteries, have attracted more and more attention. However, the existing polyolefin separators have disadvantages such as poor mechanical properties and poor heat resistance, which will lead to poor safety performance of lithium-ion batteries produced using polyethylene separators. The polyethylene separator material for battery production is an inevitable requirement for the development of the current lithium ion industry. At present, the main ways to improve the polyethylene base separator are surface modification and surface coating.

Reference document 1: CN103378331B discloses a lithium battery separator and its preparation method. The lithium battery separator is a three-layer composite membrane, with a nuclear pore membrane as the base material, a high temperature resistant layer compounded on the nuclear pore membrane, and a high temperature resistant layer compounded with As for the heat sealing layer, the high temperature resistant layer can withstand a high temperature above 200°C, and the melting point of the heat sealing layer is between 100°C and 130°C. When the composite membrane is heated to 200°C, the nuclear pore membrane layer basically melts, and the high-temperature resistant layer can still form a film, which has high thermal stability. In the process of charging and discharging, even if the organic bottom film melts, the high-temperature resistant layer can still maintain The integrity of the diaphragm prevents the occurrence of large-area positive/negative short circuit and improves the safety of the battery. The lithium battery separator disclosed in this reference document is about performing surface coating on the substrate separator to form a three-layer composite film to improve the high temperature resistance performance of the separator.

Reference document 2: CN106876641A discloses a lithium battery separator and its preparation method and application in lithium batteries. The separator is an inorganic nanofiber film, and the inorganic components can enhance the thermal dimensional stability of the lithium battery separator. High heat resistance and stability, inorganic components can improve the wettability of lithium battery separator and electrolyte, and the high porosity of inorganic nanofiber membrane can improve the electrolyte absorption rate and ion conductivity of lithium battery separator, which is beneficial to improve Cycle and rate performance of lithium batteries.

None of the lithium-ion batteries provided in the above reference documents can achieve higher temperature discharge, and their application has certain environmental limitations. The present invention intends to provide a titaniumized diaphragm to improve the high-temperature discharge performance of lithium-ion batteries, and can realize ultra-high-temperature lithium batteries with good discharge performance under high-temperature conditions of 85°C; the successful research of this ultra-high-temperature lithium battery has contributed to the promotion The development of new energy vehicles is of great significance.

Utility model content

The technical problem to be solved by the utility model is to provide a titanium diaphragm ultra-high temperature lithium battery that can still achieve good discharge performance under the high temperature condition of 85°C.

In order to solve the above technical problems, the utility model adopts the following technical solutions:

A titanium diaphragm ultra-high temperature lithium battery is provided, including a casing and a positive electrode, a negative electrode, a diaphragm and an electrolyte disposed in the casing; the diaphragm is disposed between the positive electrode and the negative electrode; the electrolyte is filled in the casing;

The diaphragm is a titaniumized diaphragm, and the titaniumized diaphragm may be a titaniumized polyethylene diaphragm or a titaniumized polypropylene diaphragm.

Specifically, it may be a porous titaniumized polyethylene membrane or a porous titaniumized polypropylene membrane obtained by titaniumizing a porous polyethylene membrane base or a porous polypropylene membrane base.

further,

The thickness of the titaniumized diaphragm is between 8 μm and 15 μm.

further,

The pore diameter of the titaniumized diaphragm is 0.3 μm to 2.5 μm, and the pore density is 6×10 ⁶ cm ⁻² to 5×10 ⁸ cm ⁻² .

further,

The lithium battery also includes a positive tab and a negative tab, one end of the positive tab is connected to the positive pole, and the other end of the positive tab is exposed from the casing; one end of the negative tab is connected to the negative pole, and the other end of the negative tab is connected to the negative pole. reveal the shell.

further,

The shell includes upper and lower layers of aluminum foil and a middle nylon layer, each layer is connected by an adhesive layer, and the thickness of the aluminum foil layer is 20-25 μm.

further,

The lithium battery also includes insulating sheet 1 and insulating sheet 2 arranged at the connection between the shell and the positive tab and the negative tab.

The beneficial effects of the utility model:

The use of titaniumized polyethylene or polypropylene separators in lithium batteries has the following advantages, which can improve the safety of lithium batteries; increase the high-temperature conductivity of lithium batteries; improve the service life of lithium batteries, increase the number of cycles of lithium batteries, and improve Thermal stability of lithium batteries. Improve the self-discharge performance of lithium batteries; enhance the surface hardness of polymer lithium batteries.

The lithium battery of the present invention can achieve good discharge performance at a high temperature of 85°C by using a titanium diaphragm, and can be well applied to the manufacture and use of power batteries for new energy vehicles, which is important for promoting the development of new energy vehicles significance. Since lithium battery is a kind of green energy, it also plays an important role in energy saving and environmental protection.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are only some embodiments of the utility model, and those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is a schematic structural diagram of an ultra-high temperature lithium battery according to an embodiment of the present invention;

Figure 2.1 is a schematic diagram of the size of the ultra-high temperature lithium battery in the embodiment of the present invention;

Figure 2.2 is the second schematic diagram of the size of the ultra-high temperature lithium battery in the embodiment of the utility model;

Figure 2.3 is the third schematic diagram of the size of the ultra-high temperature lithium battery in the embodiment of the utility model;

The above reference signs:

Shell 1; positive pole 2; negative pole 3; diaphragm 4; positive pole ear 51; negative pole ear 52; positive insulating sheet 61; negative insulating sheet 62.

T is the thickness of the battery; W is the width of the battery; L is the length of the battery; L2 is the length of the insulating sheet exposed from the edge of the casing; L3 is the length of the positive (negative) tab exposed from the insulating sheet; W' is the distance between the positive and negative tabs d is the width of the positive (negative) tab; a1 is the angle between the positive tab and the horizontal direction of the shell; a2 is the angle between the negative tab and the horizontal direction of the shell.

Detailed ways

The utility model is further described below in conjunction with the accompanying drawings and embodiments, but it is not used to limit the scope of the utility model.

As shown in Figures 1 and 2.1-2.3, this embodiment provides a titanium diaphragm ultra-high temperature lithium battery, including a casing 1 and a positive electrode 2, a negative electrode 3, a diaphragm 4 and an electrolyte disposed in the casing 1; the diaphragm 4 is provided Between the positive electrode 2 and the negative electrode 3; the electrolyte is filled in the casing 1;

The diaphragm is a titaniumized diaphragm, and the titaniumized diaphragm may be a titaniumized polyethylene diaphragm or a titaniumized polypropylene diaphragm.

Specifically, it may be a porous titaniumized polyethylene membrane or a porous titaniumized polypropylene membrane obtained by titaniumizing a porous polyethylene membrane base or a porous polypropylene membrane base.

The thickness of the titaniumized diaphragm is between 8 μm and 15 μm.

The pore diameter of the titaniumized polyethylene diaphragm or the titaniumized polypropylene diaphragm is 0.3 μm to 2.5 μm, and the pore density is 6×10 ⁶ cm ⁻² to 5×10 ⁸ cm ⁻² .

The lithium battery also includes a positive tab 51 and a negative tab 52, one end of the positive tab 51 is connected to the positive pole 2, and the other end of the positive tab 51 exposes the casing 1; one end of the negative tab 52 is connected to the negative pole 3, and the negative pole The other end of the ear 52 reveals the housing 1 .

The casing 1 includes upper and lower layers of aluminum foil and a middle nylon layer, each layer is connected by an adhesive layer, and the thickness of the aluminum foil layer is 20-25 μm.

The lithium battery also includes an insulating sheet 1 61 and an insulating sheet 2 62 arranged at the connection between the casing 1 and the positive tab 51 and the negative tab 52 .

The specific dimensions and technical parameters of the ultra-high temperature lithium battery with titanium diaphragm provided in this example are as follows:

Rated capacity: 2900mAh; rated voltage 3.7V.

Specifications and dimensions are as follows:

In this embodiment, the polyethylene or polypropylene diaphragm after titaniumization is used for lithium batteries and has the following benefits, which can improve the safety of lithium batteries; increase the high-temperature conductivity of lithium batteries; improve the service life of lithium batteries and increase the life of lithium batteries. cycle times, improving the thermal stability of lithium batteries. Improve the self-discharge performance of lithium batteries; enhance the surface hardness of polymer lithium batteries.

The lithium battery of this embodiment can achieve good discharge performance at a high temperature of 85°C by using a titanium diaphragm, and can be well applied to the manufacture and use of power batteries for new energy vehicles, and has a positive effect on promoting the development of new energy vehicles. important meaning. Since lithium battery is a kind of green energy, it also plays an important role in energy saving and environmental protection.

The basic principles, main features and advantages of the present utility model have been shown and described above. Those skilled in the industry should understand that the utility model is not limited by the above-mentioned embodiments. The above-mentioned embodiments and descriptions only illustrate the principle of the utility model. The utility model does not depart from the spirit and scope of the utility model There will also be various changes and improvements, and these changes and improvements all fall within the scope of the claimed utility model. The scope of protection required by the utility model is defined by the appended claims and their equivalents.

Claims (6)

1. A titanium diaphragm ultra-high temperature lithium battery, characterized in that, It includes a casing and a positive electrode, a negative electrode, a diaphragm and an electrolyte disposed in the casing; the diaphragm is arranged between the positive electrode and the negative electrode; the electrolyte is filled in the casing; The diaphragm is a titaniumized diaphragm, and the titaniumized diaphragm may be a titaniumized polyethylene diaphragm or a titaniumized polypropylene diaphragm. 2. A titaniumized diaphragm ultra-high temperature lithium battery according to claim 1, characterized in that, The thickness of the titaniumized diaphragm is between 8 μm and 15 μm. 3. A titaniumized diaphragm ultra-high temperature lithium battery according to claim 1, characterized in that, The pore diameter of the titaniumized diaphragm is 0.3 μm to 2.5 μm, and the pore density is 6×10 ⁶ cm ⁻² to 5×10 ⁸ cm ⁻² . 4. A titaniumized diaphragm ultra-high temperature lithium battery according to claim 1, characterized in that, The lithium battery also includes a positive tab and a negative tab, one end of the positive tab is connected to the positive pole, and the other end of the positive tab is exposed from the casing; one end of the negative tab is connected to the negative pole, and the other end of the negative tab is connected to the negative pole. reveal the shell. 5. A titaniumized diaphragm ultra-high temperature lithium battery according to claim 1, characterized in that, The shell includes upper and lower layers of aluminum foil and a middle nylon layer, each layer is connected by an adhesive layer, and the thickness of the aluminum foil layer is 20-25 μm. 6. A titaniumized diaphragm ultra-high temperature lithium battery according to claim 1, characterized in that, The lithium battery also includes insulating sheet 1 and insulating sheet 2 arranged at the connection between the shell and the positive tab and the negative tab.