CN208093666U - Three-electrode lithium battery - Google Patents

Abstract

The utility model discloses a three-electrode lithium battery. The positive pole mechanism includes a positive pole tab and a positive pole piece. The positive pole pole piece is connected with the positive pole piece. The positive pole piece is located in the electrolyte solution. It is connected to the negative electrode, the negative electrode is located in the electrolyte, the first diaphragm is located between the positive electrode and the negative electrode, the reference electrode is located on the side of the positive electrode mechanism away from the negative electrode mechanism, and the reference electrode mechanism includes reference electrode lugs, copper foil and Lithium foil, the reference electrode tab is connected to the copper foil, the copper foil is located in the electrolyte, the second diaphragm is located between the copper foil and the positive electrode, and the lithium foil is fixed on the copper foil; the three-electrode lithium battery proposed by the utility model, Lithium foil is carried by copper foil as a reference electrode, which greatly prolongs the effective use time of the reference electrode and ensures that the reference electrode will not fail during the long-term monitoring of the positive and negative voltages; the commonly used lithium plating process is omitted, It greatly simplifies the manufacturing process of the three electrodes of the lithium battery.

Description

A three-electrode lithium battery

technical field

The utility model relates to the field of lithium batteries, in particular to a three-electrode lithium battery.

Background technique

At present, the lithium battery industry is developing rapidly, and various methods of researching lithium batteries are also emerging. The lithium reference electrode is introduced into the lithium battery, and the positive and negative electrode potential changes can be monitored separately when the lithium battery is working normally. Therefore, the reference electrode is used in lithium batteries. It has a wide range of applications in mechanism research, battery design, and impedance separation.

At present, the three electrodes of lithium batteries are mainly made by placing copper wires on the diaphragm, and after the battery is packaged and prepared, the copper wires are plated with lithium, so that a layer of lithium metal is attached to the copper surface, but the disadvantage is that the reference electrode is difficult to maintain. For a long time, because the layer of lithium plated is relatively thin, it will be exhausted after long-term charging and discharging. If the lithium plating time is prolonged, problems such as lithium dendrites will appear.

Utility model content

In order to solve the technical problems in the background technology, the utility model proposes a three-electrode lithium battery.

A three-electrode lithium battery proposed by the utility model includes a positive electrode mechanism, a negative electrode mechanism, a reference electrode mechanism, a first diaphragm, a second diaphragm and an electrolyte;

The positive electrode mechanism includes a positive electrode lug and a positive electrode sheet, the positive electrode ear is connected to the positive electrode sheet, and the positive electrode sheet is located in the electrolyte;

The negative electrode mechanism includes a negative electrode tab and a negative electrode sheet, the negative electrode tab is connected to the negative electrode sheet, the negative electrode sheet is located in the electrolyte, and the first separator is located between the positive electrode sheet and the negative electrode sheet to isolate the positive electrode sheet and the negative electrode sheet;

The reference electrode mechanism is located on the side of the positive electrode mechanism away from the negative electrode mechanism. The reference electrode mechanism includes the reference electrode lug, copper foil and lithium foil. The reference electrode lug is connected to the copper foil, and the lithium foil is fixed on the copper foil. and the lithium foil are located in the electrolyte, and the second diaphragm is located between the copper foil and the positive electrode sheet for isolating the copper foil and the positive electrode sheet.

Preferably, the lithium foil has a smaller surface area than the copper foil.

Preferably, the side of the copper foil away from the lithium foil is fixed on the second separator.

In the utility model, the proposed three-electrode lithium battery has the following advantages:

1. The lithium foil is carried by the copper foil as the reference electrode, which greatly prolongs the effective use time of the reference electrode and ensures that the reference electrode will not fail during the long-term monitoring of the positive and negative voltages;

2. Directly place the lithium foil in the pouch battery to prepare the reference electrode of the pouch battery, omitting the commonly used lithium plating process, which greatly simplifies the manufacturing process of the three electrodes of the lithium battery;

3. Copper foil is used as the lithium foil carrier, which not only solves the problem of drawing out the reference electrode, but also avoids the soft lithium metal from breaking during the monitoring process.

Description of drawings

FIG. 1 is a schematic structural view of a three-electrode lithium battery proposed by the present invention.

Detailed ways

As shown in FIG. 1 , FIG. 1 is a schematic structural diagram of a three-electrode lithium battery proposed by the present invention.

Referring to Fig. 1, a kind of three-electrode lithium battery that the utility model proposes, comprises positive electrode mechanism, negative electrode mechanism, reference electrode mechanism, first separator 4, second separator 5 and electrolyte; The lithium battery in the present embodiment is soft Lithium-packed battery, soft-packed lithium battery is a rectangular parallelepiped structure;

The positive electrode mechanism includes a positive electrode tab 11 and a positive electrode sheet 12, the positive electrode tab 11 and the positive electrode sheet 12 are connected by welding, the positive electrode tab 11 extends to the outside of the lithium battery, and the positive electrode sheet 12 is soaked in the electrolyte;

The negative electrode mechanism includes a negative electrode tab 21 and a negative electrode sheet 22. The negative electrode tab 21 and the negative electrode sheet 22 are connected by welding. The negative electrode tab 21 extends to the outside of the lithium battery. The negative electrode sheet 22 is located in the electrolyte. With a set distance, the first separator 4 is located between the positive electrode sheet 12 and the negative electrode sheet 22 for isolating the positive electrode sheet 12 and the negative electrode sheet 22;

The reference electrode mechanism is located on the side of the positive electrode mechanism away from the negative electrode mechanism. The reference electrode mechanism includes a reference electrode tab 31, a copper foil 32 and a lithium foil 33. The reference electrode tab 31 and the copper foil 32 are connected by welding. The electrode lug 31 extends to the outside of the lithium battery, the copper foil 32 is located in the electrolyte, there is a set distance between the copper foil 32 and the positive electrode sheet 12, and the second separator 5 is located between the copper foil 32 and the positive electrode sheet 12 for isolating copper. The foil 32, the negative electrode sheet 22, and the lithium foil 33 are fixed on the copper foil 32 by green glue.

In this embodiment, the function of the copper foil 32 is to fix the lithium foil 33, so the surface area of the lithium foil 33 is smaller than the surface area of the copper foil 32, and the whole lithium foil 33 falls on the copper foil 32, so as to avoid softness during the monitoring of the positive and negative potential changes. Lithium metal fractures.

The above is only a preferred embodiment of the utility model, but the scope of protection of the utility model is not limited thereto. Any equivalent replacement or change of the new technical solution and the concept of the utility model shall be covered by the protection scope of the utility model.

Claims (3)

1. a kind of three electrode lithium batteries, which is characterized in that including positive mechanism, cathode mechanism, reference electrode mechanism, the first diaphragm (4), the second diaphragm (5) and electrolyte；

Positive mechanism includes positive pole ear (11) and positive plate (12), and positive pole ear (11) is connect with positive plate (12), positive plate (12) it is located in electrolyte；

Cathode mechanism includes negative lug (21) and negative plate (22), and negative lug (21) is connect with negative plate (22), negative plate (22) it is located in electrolyte, the first diaphragm (4) is located between positive plate (12) and negative plate (22) for positive plate (12) to be isolated With negative plate (22)；

Reference electrode mechanism is located at positive mechanism far from cathode mechanism side, and reference electrode mechanism includes reference electrode lug (31), copper foil (32) and lithium foil (33), reference electrode lug (31) are connect with copper foil (32), and lithium foil (33) is fixed on copper foil (32) On, copper foil (32) and lithium foil (33) are located in electrolyte, and the second diaphragm (5), which is located between copper foil (32) and positive plate (12), to be used for Copper foil (32) and positive plate (12) is isolated.

2. three electrodes lithium battery according to claim 1, which is characterized in that lithium foil (33) surface area is less than copper foil (32) table Area.

3. three electrodes lithium battery according to claim 1, which is characterized in that copper foil (32) is fixed far from lithium foil (33) side On the second diaphragm (5).