阅读说明：本技术 一种电池集电子电阻焊工艺 (Battery collector electron resistance welding process ) 是由 常海涛 严瑞兴 沈健焕 于 2021-09-08 设计创作，主要内容包括：本发明公开了一种电池集电子电阻焊工艺,充分考虑镀层对焊接质量和焊接飞溅造成的影响,将焊接过程细分为三段,其中焊接一段采用低功率使所述负极盖的镀层融化但不破坏所述铜针的母材,焊接二段提升功率,将所述负极盖和所述铜针焊接牢固形成所述集电子,由于冷却切换阶段在不放电的状态切换焊接参数,使经焊接一段融化的所述负极盖的镀层冷却至呈固液共存状态,减小了焊点处的电阻,在焊接二段时的功率比传统恒定电流电阻焊的强行焊接功率小,有效减少铜粉飞溅,明显改善了电池生产线的环境。(The invention discloses a battery electron collecting resistance welding process, which fully considers the influence of a plating layer on welding quality and welding spatter, subdivides a welding process into three sections, wherein the welding section adopts low power to melt the plating layer of a negative electrode cover without damaging a base metal of a copper needle, the power is increased by the welding section, the negative electrode cover and the copper needle are firmly welded to form electron collecting, welding parameters are switched in a non-discharge state in a cooling switching stage, the plating layer of the negative electrode cover melted by the welding section is cooled to be in a solid-liquid coexisting state, the resistance at a welding point is reduced, the power during the welding of the section is lower than the forced welding power of the traditional constant current resistance welding, copper powder spatter is effectively reduced, and the environment of a battery production line is obviously improved.)

1. The utility model provides a battery collector electron resistance welds technology, its adopts the spot welder to weld the negative pole lid and the copper needle of battery, its characterized in that: which comprises the following steps:

(1) welding a section: the negative electrode cover is in close contact with the copper needle under the pressure of the spot welding machine, then an electrode of the spot welding machine is connected, the plating layer of the negative electrode cover is melted by resistance heating, and the power of the spot welding machine is limited by the condition that the plating layer of the negative electrode cover is melted but the base material of the copper needle is not damaged;

(2) cooling and switching: stopping discharging by the spot welding machine to switch welding parameters, and cooling the plating layer of the cathode cover melted in the step (1) to be in a solid-liquid coexisting state;

(3) and (3) welding a second section: and increasing the power of the spot welding machine to melt the contact surface of the negative electrode cover and the copper needle, and firmly welding the negative electrode cover and the copper needle to form a battery electron collector.

2. The battery collecting electron resistance welding process according to claim 1, characterized in that: the welding section is electrified by adopting constant voltage control, and the welding section is electrified by adopting constant current control.

3. The battery collecting electron resistance welding process according to claim 1, characterized in that: and the welding first section and the welding second section are electrified by adopting constant current control.

4. The battery collecting electron resistance welding process according to claim 1, characterized in that: the welding section is electrified by adopting constant current control, and the welding section is electrified by adopting constant voltage control.

5. The battery collecting electron resistance welding process according to claim 1, characterized in that: and the welding first section and the welding second section are electrified by adopting constant voltage control.

6. The battery collecting electron resistance welding process according to claim 1, characterized in that: and when the original welding time of the spot welding machine cannot meet the electron collecting resistance welding process, the distance between the initial discharge position and the final discharge position is prolonged.

Technical Field

The invention relates to a battery welding process, in particular to a battery collector electron resistance welding process.

Background

The alkaline battery is a high-capacity dry battery which takes manganese dioxide as a positive electrode, zinc as a negative electrode and potassium hydroxide as electrolyte. The current collector of the alkaline battery structure on the market consists of a copper needle, a sealing ring and a negative cover. When assembling the current collector, the negative electrode cover and the copper needle are welded into an integrated electron, and then the copper needle in the integrated electron is inserted into the central column through hole of the sealing ring by using stamping equipment to form the current collector.

Resistance welding is commonly performed on the negative electrode cover and the copper needle by using a spot welding machine in the industry. The conventional resistance welding process comprises constant current control resistance welding and constant voltage control resistance welding, wherein the constant current control resistance welding process is a main using method in the resistance welding industry due to strong adaptability of the constant current control resistance welding process to products with unstable plating layers. Generally, the surfaces of the base material of the negative electrode cover and the base material of the copper needle are both provided with electroplated layers, and the thickness of the electroplated layers of the negative electrode cover reaches 2.5-5 um. In order to overcome the coating fluctuation of the cathode cover and ensure the welding strength in the welding process, large current and long welding time need to be set, so that the heating in the welding process is large, and the problem of severe welding copper powder splashing in a workshop is caused. Because the copper powder is produced in a large amount, a workshop spends a large amount of time to ensure the machine sanitation, a plurality of optical fiber faults and other problems are derived, and the production continuity and the start-up rate are influenced; on the other hand, copper powder is dust, and a large amount of copper powder easily pollutes the manufacturing environment of a production line, and if the copper powder falls to a positive ring or the vicinity of isolation paper, the isolation paper is easily punched, so that the quality problem of the battery is caused.

In view of this, there is a need to innovate an electron-integrated soldering process to minimize the generation of copper powder while ensuring the soldering strength.

Disclosure of Invention

The invention aims to provide a battery current collector resistance welding process.

The technical scheme for realizing the purpose of the invention is as follows: a battery collector electron resistance welding process adopts a spot welding machine to weld a battery cathode cover and a copper needle, and comprises the following steps:

(1) welding a section: the negative electrode cover is in close contact with the copper needle under the pressure of the spot welding machine, then an electrode of the spot welding machine is connected, the plating layer of the negative electrode cover is melted by resistance heating, and the power of the spot welding machine is limited by the condition that the plating layer of the negative electrode cover is melted but the base material of the copper needle is not damaged;

(2) cooling and switching: stopping discharging by the spot welding machine to switch welding parameters, and cooling the plating layer of the cathode cover melted in the step (1) to be in a solid-liquid coexisting state;

(3) and (3) welding a second section: increasing the power of the spot welder to melt the contact surface of the negative electrode cover and the copper needle, and firmly welding the negative electrode cover and the copper needle to form the battery current collector;

further, the welding section is electrified by adopting constant voltage control, and the welding section is electrified by adopting constant current control.

Further, the welding first section and the welding second section are electrified by adopting constant current control.

Further, the welding section is electrified by adopting constant current control, and the welding section is electrified by adopting constant voltage control.

Further, the welding first section and the welding second section are electrified by adopting constant voltage control.

Further, when the factory-set welding time of the spot welding machine cannot meet the electron collecting resistance welding process, the distance between the initial discharge position and the final discharge position is prolonged, so that the welding time is prolonged.

According to the material characteristics of the negative electrode cover, the influence of the plating layer on the welding quality and the welding spatter is fully considered, the welding process is subdivided into three sections, wherein the low power is adopted for the first welding section to melt the plating layer of the negative electrode cover but not to damage the base metal of the copper needle, then the cooling switching is carried out to cool the plating layer of the negative electrode cover melted in the step (1) to be in a solid-liquid coexisting state, then the power is increased for the second welding section relative to the first welding section, and the negative electrode cover and the copper needle are further welded firmly to form the electron collector. Because the welding parameters are switched in the non-discharge state in the cooling switching stage, the coating of the cathode cover which is melted by the welding section is cooled to be in a solid-liquid coexisting state, the resistance at the welding point is reduced, and the power during the welding section is lower than the forced welding power of the traditional constant current resistance welding due to the reduction of the resistance at the welding point, so that the splashing of copper powder is effectively reduced, and the environment of a battery production line is obviously improved.

Detailed Description

The following is a detailed description of the preferred embodiments of the invention.

Example 1

A battery collector electron resistance welding process adopts a spot welding machine to weld a negative electrode cover and a copper needle, the power supply of the spot welding machine is a power supply of Mi subunit power supply model IPB-5000A, and the process comprises the following steps:

(1) welding a section: the negative electrode cover is closely contacted with the copper needle under the pressure of the spot welding machine, then the electrode of the spot welding machine is connected, the plating layer of the negative electrode cover in the contact surface of the negative electrode cover and the copper needle is melted by using resistance heating, and the power of the spot welding machine is limited by the condition that the plating layer of the negative electrode cover is melted but the base material of the copper needle is not damaged; the welding section is electrified by adopting constant voltage control, the welding voltage is 1.5V, and the welding time is 2ms (including slow rising time 1 ms);

(2) cooling and switching: stopping discharging for 1ms by the spot welding machine to switch welding parameters, and cooling the plating layer of the cathode cover melted in the step (1) to be in a solid-liquid coexisting state;

(3) and (3) welding a second section: increasing the power of the spot welder to melt the contact surface of the negative electrode cover and the copper needle, and firmly welding the negative electrode cover and the copper needle to form the electron collection body; the welding second section is electrified by adopting constant current control, the welding current is 2KA, and the welding time is 8ms (including slow-rise time 2 ms);

the total welding time was 11 ms. The slow-rise time is set to prevent overcurrent conditions such as copper needle welding burn and bottom cover welding explosion caused by too high welding speed.

Examples 2 to 9

Examples 2-9 used the same power supply and electron collecting resistance welding process as in example 1, with the same cooling switching times, but with different process parameters for the first and second welding stages, as shown in Table 1

Example 10

A battery collector electron resistance welding process adopts a spot welding machine to weld a negative electrode cover and a copper needle, wherein the power supply of the spot welding machine IS a power supply of Mi subunit type IS-120B, and the process comprises the following steps:

(1) welding a section: the negative electrode cover is closely contacted with the copper needle under the pressure of the spot welding machine, then the electrode of the spot welding machine is connected, the plating layer of the negative electrode cover in the contact surface of the negative electrode cover and the copper needle is melted by using resistance heating, and the power of the spot welding machine is limited by the condition that the plating layer of the negative electrode cover is melted but the base material of the copper needle is not damaged; the welding section is electrified by adopting constant current control, the welding current is 1.5KA, and the welding time is 4ms (including slow rising time 2 ms);

(2) cooling and switching: stopping discharging for 1ms by the spot welding machine to switch welding parameters, and cooling the plating layer of the cathode cover melted in the step (1) to be in a solid-liquid coexisting state;

(3) and (3) welding a second section: increasing the power of the spot welder to melt the contact surface of the negative electrode cover and the copper needle, and firmly welding the negative electrode cover and the copper needle to form the electron collection body; the welding second section is electrified by adopting constant current control, the welding current is 2.8KA, and the welding time is 8 ms;

the total welding time was 13 ms.

Examples 11 to 13

Examples 11-13 used the same power supply and electron collecting resistance welding process as in example 10, the same cooling switching times, but different process parameters, as shown in Table 2

TABLE 2

Example 14

A battery collector electron resistance welding process adopts a spot welding machine to weld a negative electrode cover and a copper needle, the power supply of the spot welding machine is a power supply of Mi subunit power supply model IPB-5000A, and the process comprises the following steps:

(1) welding a section: the negative electrode cover is closely contacted with the copper needle under the pressure of the spot welding machine, then the electrode of the spot welding machine is connected, the plating layer of the negative electrode cover in the contact surface of the negative electrode cover and the copper needle is melted by using resistance heating, and the power of the spot welding machine is limited by the condition that the plating layer of the negative electrode cover is melted but the base material of the copper needle is not damaged; the welding section is electrified by adopting constant current control, the welding current is 1.7 KA, and the welding time is 4ms (including slow rising time 2 ms);

(2) cooling and switching: stopping discharging for 1ms by the spot welding machine to switch welding parameters, and cooling the plating layer of the cathode cover melted in the step (1) to be in a solid-liquid coexisting state;

(3) and (3) welding a second section: increasing the power of the spot welder to melt the contact surface of the negative electrode cover and the copper needle, and firmly welding the negative electrode cover and the copper needle to form the electron collection body; the welding second section adopts constant voltage control to carry out electrification, the welding voltage is 4.85V, and the welding time is 9ms (including slow rising time 3 ms)

The total welding time was 10 ms.

Examples 15 to 17

Examples 15-17 used the same collector electron resistance welding process as in example 14, with the same cooling switching time, but with slightly different power and process parameters, as shown in Table 3

TABLE 3

Example 18

A battery collector electron resistance welding process adopts a spot welding machine to weld a negative electrode cover and a copper needle, wherein the power supply of the spot welding machine IS a power supply of Mi subunit type IS-120B, and the process comprises the following steps:

(1) welding a section: the negative electrode cover is closely contacted with the copper needle under the pressure of the spot welding machine, then the electrode of the spot welding machine is connected, the plating layer of the negative electrode cover in the contact surface of the negative electrode cover and the copper needle is melted by using resistance heating, and the power of the spot welding machine is limited by the condition that the plating layer of the negative electrode cover is melted but the base material of the copper needle is not damaged; the welding section is electrified by adopting constant voltage control, the welding voltage is 1.5V, and the welding time is 2ms (including slow rising time 1 ms);

(2) cooling and switching: stopping discharging for 1ms by the spot welding machine to switch welding parameters, and cooling the plating layer of the cathode cover melted in the step (1) to be in a solid-liquid coexisting state;

(3) and (3) welding a second section: increasing the power of the spot welder to melt the contact surface of the negative electrode cover and the copper needle, and firmly welding the negative electrode cover and the copper needle to form the electron collection body; and the welding second section is electrified by adopting constant voltage control, the welding voltage is 3.75V, and the welding time is 8 ms.

The total welding time was 11.

Examples 19 to 25

Examples 19-25 used the same power supply and electron collecting resistance welding process as in example 18, but the cooling switching times were the same, except for the process parameters, as shown in table 4.

TABLE 4

Comparative example 1

Comparative example 1 a single-stage constant voltage resistance welding process was used with a welding voltage of 2.1V, a welding time of 8ms, and a power of 14.5 KW. Wherein, the power supply of the spot welder is a Mi subunit power supply type IPB-5000A power supply.

Comparative example 2

Comparative example 2 a single-stage constant current resistance welding process was used with a welding current of 3.3KA, a welding time of 8ms, and a power of 14.1 KW. Wherein the power supply of the spot welding machine IS a Mi subunit power supply model IS-120B power supply.

The above examples are modified examples and comparative examples of a high-speed spot welding machine, wherein the power of the first welding section in example 5 is 0.3KW, and the power of the second welding section is 12KW, which is obviously smaller than that of comparative example 1; the power of example 10 in the first welding stage was 0.43KW and the power of the second welding stage was 12KW, which is significantly lower than that of comparative example 2. The adoption of the collector electron resistance welding process can reduce the copper powder in the welding process by about 50 percent, greatly reduce the management burden of workshop sanitation and obviously improve the manufacturing environment of a battery production line.

Because the welding time of high-speed resistance welding is very short, a spot welding machine cannot collect data to correct and compensate welding parameters at any time in the welding process, and if the original welding time of the spot welding machine cannot meet the integrated electronic resistance welding process, the welding time can be increased by prolonging the distance between the initial discharge position and the final discharge position.

The invention aims to fully consider the influence of a plating layer on welding quality and welding spatter according to the material characteristics of a cathode cover, subdivide a welding process into three sections, thereby avoiding the defect of forced welding of the traditional constant current resistance welding and reducing the generation of copper powder impurities.

The above description is only an embodiment of the present invention, and not intended to limit the scope of the present invention, and all equivalent flow transformations made by the present specification, or directly or indirectly applied to other related technical fields, are included in the scope of the present invention.