Liquid injection system and liquid injection method of battery

Abstract

The embodiment of the invention provides a liquid injection system and a liquid injection method of a battery. The liquid injection system comprises a mounting seat, a liquid injection module and a weighing module, the liquid injection module comprises a tray and a liquid injection cup. And the weighing module is arranged on the mounting seat. Wherein the liquid injection cup has a pre-assembling state and an assembling state. And when the liquid injection cup is in the pre-assembling state, the liquid injection cup is pre-assembled on the tray. The weight of the liquid injection cup is borne by the tray. And when the liquid injection cup is in the assembly state, the liquid injection cup is assembled on the weighing module. The weight of the liquid injection cup is borne by the weighing module. The weighing module is used for weighing the liquid injection cup. According to the liquid injection system, the weighing module is arranged and used for weighing the liquid injection cup in real time so as to obtain the injection amount of the electrolyte in the liquid injection cup. A liquid injection pump is not needed to control the liquid injection amount, and meanwhile, the bubble removal action is not needed, so that the liquid preparation efficiency is improved. And the electrolyte in the electrolyte room can be directly injected into the electrolyte injection cup after being filtered by the filter, so that the occupied space is reduced, and the cost is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of batteries, and particularly to a liquid injection system and a liquid injection method for a battery. Background Art

[0002] This section aims to provide background or context for the embodiments of the present application. The descriptions herein are not admitted to be prior art merely because they are included in this section.

[0003] In related technologies, a liquid storage tank needs to be provided to store the electrolyte transported from the electrolyte room. A liquid injection pump quantitatively pumps the electrolyte in the liquid storage tank into a receiving device. After the battery is evacuated, the liquid injection valve of the receiving device is opened, and the electrolyte in the receiving device is injected into the liquid injection cup. It can be seen that each liquid injection cup requires a corresponding liquid injection pump, and a liquid storage tank and a receiving device need to be provided to store the electrolyte transported from the electrolyte room, occupying space and increasing equipment costs. In addition, by using the liquid injection pump to control the injection volume of the electrolyte, the bubbles in the electrolyte will reduce the control accuracy of the electrolyte injection volume, and the electrolyte also needs to be degassed and filtered for impurities, reducing the liquid preparation efficiency. Summary of the Invention

[0004] In view of this, the embodiments of the present application are expected to provide a liquid injection system and a liquid injection method for a battery, which do not require a liquid injection pump to control the injection volume and do not require a degassing operation, reducing costs and occupied space and improving the liquid preparation efficiency.

[0005] To achieve the above object, a first aspect of the embodiments of the present application provides a liquid injection system for a battery, including:

[0006] A mounting base;

[0007] A liquid injection module, including a tray and a liquid injection cup;

[0008] A weighing module, disposed on the mounting base;

[0009] Wherein, the liquid injection cup includes a pre-installed state and an assembled state. In the pre-installed state of the liquid injection cup, the liquid injection cup is pre-installed on the tray, and the weight of the liquid injection cup is borne by the tray; in the assembled state of the liquid injection cup, the liquid injection cup is assembled onto the weighing module, and the weight of the liquid injection cup is borne by the weighing module, and the weighing module is used to weigh the liquid injection cup.

[0010] The liquid injection system of the battery provided by the embodiment of the present application includes a mounting base, a liquid injection module, and a weighing module. The liquid injection cup has a pre-installed state and an assembled state. When the liquid injection cup is in the pre-installed state, the liquid injection cup is pre-installed on the tray. At this time, the weight of the liquid injection cup is borne by the tray. When the liquid injection cup is in the assembled state, the liquid injection cup is assembled onto the weighing module. At this time, the weight of the liquid injection cup is borne by the weighing module, and the weighing module is used to weigh the liquid injection cup. That is to say, by setting the weighing module to weigh the liquid injection cup, that is, the weighing module can weigh the liquid injection cup in real time to obtain the amount of electrolyte injected into the liquid injection cup. There is no need for a liquid injection pump to control the liquid injection volume, and there is no need for a de-bubbling operation, thereby improving the liquid preparation efficiency. In addition, the electrolyte in the electrolyte room can be directly injected into the liquid injection cup after being filtered by a filter, which simplifies the structure, reduces the cost, reduces the occupied space, and improves the structural compactness of the liquid injection system.

[0011] In addition, since the real-time weight A2 of the liquid injection cup can be obtained through the weighing module after the liquid injection cup is filled (A2 refers to the weight after the electrolyte is injected into the liquid injection cup, that is, the weight of the liquid injection cup itself and the weight of the electrolyte), after injecting the electrolyte in the liquid injection cup into the battery, weighing the liquid injection cup at this time gives A3 (A3 refers to the weight of the liquid injection cup itself and the weight of the remaining electrolyte), that is, the weight of the electrolyte injected into the battery is A2 - A3. That is to say, by using the liquid injection method of the embodiment of the present application, the process of separately weighing before and after battery liquid injection can be cancelled, and the production efficiency can be improved.

[0012] In some embodiments, the tray includes at least one pre-installed support position, and the liquid injection cup includes at least one pre-installed support portion. When the liquid injection cup is in the pre-installed state, the liquid injection cup is supported on the pre-installed support position through the pre-installed support portion and is located at a first height relative to the tray.

[0013] That is to say, by setting at least one pre-installed support position on the tray and at least one pre-installed support portion on the liquid injection cup, when the liquid injection cup is in the pre-installed state, the liquid injection cup is supported on the pre-installed support position through the pre-installed support portion to realize the pre-installation of the liquid injection cup.

[0014] In some embodiments, the weighing module includes at least one assembly support position, and the liquid injection cup includes at least one assembly support portion. When the liquid injection cup is in the assembled state, the liquid injection cup is supported on the first assembly support position through the assembly support portion and is located at a second height relative to the tray, and the second height is not equal to the first height.

[0015] That is to say, by setting at least one assembly support position on the weighing module and at least one assembly support portion on the liquid injection cup, when the liquid injection cup is in the assembled state, the liquid injection cup is supported on the assembly support position through the assembly support portion to realize the assembly of the liquid injection cup.

[0016] In some embodiments, an avoidance area is provided on the tray, and the liquid injection cup passes through the avoidance area through the weighing module.

[0017] By providing an avoidance area on the tray, in the pre-installed state of the liquid injection cup, the liquid injection cup passes through the avoidance area and is supported at the pre-installed support position by the pre-installed support portion, so as to realize the pre-installation of the liquid injection cup. When the liquid injection cup is in the assembled state, the liquid injection cup is supported at the assembly support position by the assembly support portion, so as to realize the assembly of the liquid injection cup. For example, the assembly support position cooperates with the assembly support portion to lift the liquid injection cup, so that the pre-installed support portion is separated from the pre-installed support position, so that the weight of the liquid injection cup is borne by the weighing module.

[0018] In some embodiments, at least one first support post is provided on the mounting seat, at least one first support hole is provided on the tray, and the tray is supported on the first support post through the first support hole.

[0019] That is to say, the mounting seat is provided with at least one first support post, the tray is provided with at least one first support hole, and the first support hole cooperates with the first support post to enable the mounting seat to support the tray, and this connection structure is simple and reliable.

[0020] In some embodiments, at least a part of the outer side wall of the liquid injection cup is convexly provided with a pre-installed support portion. When the liquid injection cup is in the pre-installed state, the liquid injection cup is supported on the upper surface of the tray through the pre-installed support portion and is located at a first height relative to the tray.

[0021] By convexly providing at least a part of the outer side wall of the liquid injection cup with a pre-installed support portion, when the liquid injection cup is in the pre-installed state, the liquid injection cup is supported on the upper surface of the tray through the pre-installed support portion. This connection structure is simple and reliable, which is beneficial to pre-install the liquid injection cup on the tray and is also beneficial to the switching of the liquid injection cup between the pre-installed state and the assembled state.

[0022] In some embodiments, at least one second support hole is provided at the bottom of the liquid injection cup, the weighing module is arranged below the tray and includes at least one second support post; when the liquid injection cup is in the assembled state, the pre-installed support portion is spaced from the upper surface of the tray, and the liquid injection cup is supported on the second support post through the second support hole and is located at a second height relative to the tray, and the second height is not equal to the first height.

[0023] At least one second support hole is provided at the bottom of the liquid injection cup, and at least one second support post is provided on the weighing module. When the liquid injection cup is in the pre-installed state, the liquid injection cup is supported on the upper surface of the tray through the pre-installed support portion. During the process of assembling the liquid injection module onto the mounting seat, the second support post on the weighing module contacts the second support hole at the bottom of the liquid injection cup and gradually lifts the liquid injection cup, so that the pre-installed support portion of the liquid injection cup gradually moves away from the upper surface of the tray. When the tray is completely supported on the mounting seat, the weighing module completely lifts the liquid injection cup, and the liquid injection cup is separated from the tray, that is, the pre-installed support portion is spaced from the upper surface of the tray, so as to realize the switching of the liquid injection cup from the pre-installed state pre-installed on the tray to the assembled state assembled on the weighing module. At this time, the liquid injection cup is located at a second height relative to the tray.

[0024] In some embodiments, the weighing module includes a weighing device and a weighing bracket provided on the weighing device, the second support post is provided on the weighing bracket, and the weighing device is used to weigh the liquid injection cup.

[0025] That is to say, by setting the weighing module to include a weighing device and a weighing bracket, the weighing bracket is provided on the weighing device, and the weighing bracket is provided with a second support post for contacting the second support hole at the bottom of the liquid injection cup to realize the support of the liquid injection cup, and the weighing device is located below the weighing bracket. In this way, when the weighing bracket lifts and supports the liquid injection cup below the liquid injection cup, the weighing device can weigh the liquid injection cup.

[0026] In some embodiments, the weighing module further includes a mounting plate, and the weighing device is provided on the mounting plate.

[0027] By providing the mounting plate and setting the weighing device on the mounting plate and assembling the mounting plate onto the mounting seat, it is beneficial to the assembly of the weighing device.

[0028] In some embodiments, the weighing module includes a plurality of weighing units, each weighing unit includes the weighing device and the weighing bracket, the liquid injection module includes a plurality of the liquid injection cups, and the liquid injection cups correspond to the weighing units one by one.

[0029] By setting the weighing module to include a plurality of weighing units and the weighing units corresponding to the liquid injection cups one by one, the weighing of a plurality of liquid injection cups can be realized simultaneously, improving the effect of preparing the liquid.

[0030] In some embodiments, the liquid injection module further includes a guiding member provided on the tray for guiding the movement of the liquid injection cup in its height direction.

[0031] It can be understood that when the liquid injection cup is switched from the pre-installed state pre-installed on the tray to the assembled state assembled on the weighing module, the liquid injection cup moves along its height direction. By setting the guiding member to guide the movement of the liquid injection cup along its height direction, it is possible to prevent the liquid injection cup from shifting during the jacking process and improve the reliability of the movement process of the liquid injection cup.

[0032] In some embodiments, the guiding member is a guiding bracket. A guiding groove is defined between the upper surface of the guiding bracket and the upper surface of the tray. The top wall of the guiding groove is provided with guiding columns extending towards the upper surface of the tray. A guiding hole is provided on the pre-installed supporting portion. The guiding columns are in sliding fit with the guiding holes to guide the movement of the liquid injection cup along its height direction.

[0033] By setting a guiding bracket with guiding columns and providing guiding holes on the pre-installed supporting portion so that the guiding columns are in sliding fit with the guiding holes to guide the movement of the liquid injection cup along its height direction, it is possible to prevent the liquid injection cup from shifting during the jacking process. In addition, the guiding bracket can also limit the position of the liquid injection cup and can prevent the liquid injection cup from completely detaching from the tray to a certain extent.

[0034] A second aspect of the embodiments of the present application provides a liquid injection method for a battery, which is applied to the liquid injection system of the battery described above. The liquid injection module further includes a liquid injection device and a valve opening device provided on the liquid injection cup. The valve opening device has an open state and a closed state;

[0035] The liquid injection method includes a liquid preparation step, and the liquid preparation step includes:

[0036] Obtain the initial weight A1 of the liquid injection cup through the weighing module;

[0037] Open the liquid injection valve of the liquid injection device and inject electrolyte into the liquid injection cup;

[0038] Obtain the real-time weight A2 of the liquid injection cup through the weighing module;

[0039] By comparing the size of A2 - A1 with the target weight A0, confirm whether the liquid preparation requirement is met;

[0040] If the liquid preparation requirement is met, the liquid preparation is completed.

[0041] During the process of preparing the liquid injection cup, first assemble the weighing module and the liquid injection module onto the mounting base. The liquid injection cup is switched from the pre-installed state to the assembled state, and the weight of the liquid injection cup is borne by the weighing module, which is used to weigh the liquid injection cup. The weighing module obtains the initial weight A1 of each liquid injection cup (i.e., the weight of each liquid injection cup before injecting the liquid). After weighing, the system records the initial weight A1 of each liquid injection cup, opens the liquid injection valve of the liquid injection device, and injects the electrolyte into the liquid injection cup. The real-time weight A2 of the liquid injection cup is obtained through the weighing module. The system determines whether the liquid preparation requirement is met by comparing the size of A2 - A1 with the target weight A0. If the liquid preparation requirement is met, the liquid preparation is completed. That is to say, by setting the weighing module to weigh the liquid injection cup, the injection amount of the electrolyte in the liquid injection cup can be judged, without the need for a liquid injection pump to control the injection amount, and there is no need for a defoaming operation either, thus improving the liquid preparation efficiency. In addition, the electrolyte in the electrolyte room can be directly injected into the liquid injection cup after being filtered by the filter, which simplifies the structure, reduces the cost, reduces the occupied space, and improves the structural compactness of the liquid injection system. The liquid preparation steps of this liquid injection method are highly efficient. Before the normally closed valve opening device is unlocked, the liquid injection cup is relatively sealed from the outside, ensuring that the electrolyte does not leak during liquid injection weighing. At the same time, the liquid injection weighing action can be completed when assembling the battery pack, improving the production rhythm.

[0042] In addition, since the real-time weight A2 of the liquid injection cup can be obtained through the weighing module after the liquid injection cup is filled (A2 refers to the weight after injecting the electrolyte into the liquid injection cup, that is, the weight of the liquid injection cup itself and the electrolyte), after injecting the electrolyte in the liquid injection cup into the battery, the liquid injection cup is weighed at this time to obtain A3 (A3 refers to the weight of the liquid injection cup itself and the remaining electrolyte), that is, the weight of the electrolyte injected into the battery is A2 - A3. That is to say, by adopting the liquid injection method of the embodiment of the present application, the process of separately weighing before and after battery liquid injection can be cancelled, improving the production efficiency.

[0043] In some embodiments, the determination of whether the liquid preparation requirement is met by comparing the size of A2 - A1 with the target weight A0 includes:

[0044] If A2 - A1 ≥ A0, it is determined that the liquid preparation requirement is met;

[0045] If A2 - A1 < A0, it is determined that the liquid preparation requirement is not met, and the electrolyte continues to be injected into the liquid injection cup.

[0046] That is to say, if the weight of the electrolyte injected into the liquid injection cup, A2 - A1, is greater than or equal to the target weight A0, that is, the electrolyte reserved in the liquid injection cup is sufficient to meet the amount of electrolyte required to be injected into the battery. At this time, it indicates that the liquid preparation requirement is met. On the contrary, if the weight of the electrolyte injected into the liquid injection cup, A2 - A1, is less than the target weight A0, that is, the electrolyte reserved in the liquid injection cup does not meet the amount of electrolyte required to be injected into the battery. At this time, it indicates that the liquid preparation requirement is not met, and the electrolyte is continuously injected into the liquid injection cup until the liquid preparation requirement is met.

[0047] In some embodiments, the step of confirming that the liquid preparation requirement is met when A2 - A1 ≥ A0 includes:

[0048] Determining whether to close the liquid injection valve based on the electrolyte flow rate q of the liquid injection device and the response time t of the liquid injection valve.

[0049] In the embodiments of the present application, based on the electrolyte flow rate q of the liquid injection device and the response time t of the liquid injection valve, it is determined whether to close the liquid injection valve. That is to say, the injection amount of the electrolyte within the response time of the liquid injection valve is calculated, and the liquid injection valve is closed in advance, thereby improving the accuracy of liquid preparation.

[0050] In some embodiments, the step of determining whether to close the liquid injection valve based on the electrolyte flow rate q of the liquid injection device and the response time t of the liquid injection valve includes:

[0051] If A2 - A1 + qt ≥ A0, then close the liquid injection valve;

[0052] If A2 - A1 + qt < A0, then open the liquid injection valve and continue to inject the electrolyte into the liquid injection cup.

[0053] The electrolyte flow rate q of the liquid injection device is obtained through experiments, and at the same time, the response time t of the liquid injection valve is measured. It is calculated that under normal flow rate, the injection amount of the electrolyte within the closing response time t of the liquid injection valve is qt. That is, the corrected target injection amount is the original target injection amount - the injection amount of the electrolyte within the closing response time t of the liquid injection valve, that is, A2 - A1 + qt ≥ A0. If A2 - A1 + qt < A0, at this time, it indicates that the liquid preparation requirement is not met, then the liquid injection valve is opened and the electrolyte is continuously injected into the liquid injection cup until the liquid preparation requirement is met, thereby improving the accuracy of liquid preparation.

[0054] In some embodiments, the battery includes a switching valve having an open state and a closed state. The liquid injection system further includes a vacuum pumping module independent of the liquid injection module. The liquid injection method further includes a vacuum pumping step. The liquid preparation step is before the vacuum pumping step or is carried out simultaneously with the vacuum pumping step. The vacuum pumping step includes:

[0055] Connect the evacuation pipeline of the evacuation module to the switching valve to keep the switching valve in the open state;

[0056] Control the evacuation device of the evacuation module to evacuate the battery;

[0057] After confirming the completion of evacuation, disconnect the evacuation pipeline from the switching valve to keep the switching valve in the closed state.

[0058] During evacuation, by connecting the evacuation pipeline of the evacuation module to the switching valve to keep the switching valve in the open state, controlling the evacuation device of the evacuation module to evacuate the battery, and after confirming the completion of evacuation, disconnecting the evacuation pipeline from the switching valve to keep the switching valve in the closed state, the evacuation step is completed at this time. The liquid injection system further includes an evacuation module independent of the liquid injection module. In this way, the evacuation pipeline of the evacuation module and the liquid injection pipeline of the liquid injection module do not need to be shared, avoiding the diffusion of residual electrolyte in the pipeline to other pipelines and valve bodies of the evacuation module during evacuation, resulting in blockage of the pipelines and valve bodies. And the liquid preparation step is before the evacuation step, or is carried out simultaneously with the evacuation step. In this way, the electrolyte can be injected into the liquid injection cup in advance at any time before the combination of the battery and the liquid injection cup, reducing the serial time (liquid preparation time) to improve production efficiency.

[0059] In some embodiments, the liquid injection method further includes a liquid injection step after the evacuation step and the liquid preparation step. The liquid injection step includes:

[0060] Connect the valve opening device to the switching valve to keep both the valve opening device and the switching valve in the open state;

[0061] Control the liquid injection module to inject liquid into the battery;

[0062] After confirming the completion of liquid injection, disconnect the valve opening device from the switching valve to keep both the valve opening device and the switching valve in the closed state.

[0063] During liquid injection, the lifting system brings the valve opening device of the liquid injection cup into contact with the switching valve of the battery (for example, controlling the tray of the liquid injection cup to move towards the battery, or controlling the tray of the battery to move towards the liquid injection cup). First, the valve opening device of the liquid injection cup contacts the switching valve of the battery. After contact, the formed liquid injection channel is kept sealed from the external environment. Due to the mutual acting force on the valve opening device and the switching valve, the switching valve is forced to open, and at the same time, the valve opening device is also opened under the mutual acting force. At this time, both the valve opening device and the switching valve are in the open state, and the liquid injection module is controlled to inject liquid into the battery. After confirming the completion of liquid injection, the valve opening device is disconnected from the switching valve to keep both the valve opening device and the switching valve in the closed state.

[0064] The liquid injection system of the battery provided by the embodiment of the present application, the liquid injection system includes a mounting base, a liquid injection module and a weighing module. The liquid injection cup includes a pre-installed state and an assembled state. When the liquid injection cup is in the pre-installed state, the liquid injection cup is pre-installed on the tray. At this time, the weight of the liquid injection cup is borne by the tray. When the liquid injection cup is in the assembled state, the liquid injection cup is assembled onto the weighing module. At this time, the weight of the liquid injection cup is borne by the weighing module, and the weighing module is used to weigh the liquid injection cup. By setting the weighing module, it is used to weigh the liquid injection cup. That is to say, the weighing module can weigh the liquid injection cup in real time to obtain the injection amount of the electrolyte in the liquid injection cup. There is no need for a liquid injection pump to control the liquid injection amount, and there is no need for a defoaming operation, thereby improving the liquid preparation efficiency. In addition, the electrolyte in the electrolyte room can be directly injected into the liquid injection cup after being filtered by the filter, which simplifies the structure, reduces the cost, reduces the occupied space, and improves the structural compactness of the liquid injection system.

[0065] In addition, since the real-time weight A2 of the liquid injection cup can be obtained through the weighing module after the liquid injection cup is filled (A2 refers to the weight after the electrolyte is injected into the liquid injection cup, that is, the weight of the liquid injection cup itself and the weight of the electrolyte), after injecting the electrolyte in the liquid injection cup into the battery, weighing the liquid injection cup at this time to obtain A3 (A3 refers to the weight of the liquid injection cup itself and the weight of the remaining electrolyte), that is, the weight of the electrolyte injected into the battery interior is A2 - A3. That is to say, by adopting the liquid injection method of the embodiment of the present application, the process of separately weighing before and after battery liquid injection can be cancelled, and the production efficiency can be improved. Brief Description of the Drawings

[0066] Figure 1 It is a schematic structural diagram of the first perspective of the liquid injection system of the battery according to an embodiment of the present application, wherein the liquid injection cup is in the assembled state;

[0067] Figure 2 It is a schematic structural diagram of the second perspective of the liquid injection system of the battery according to an embodiment of the present application, wherein the liquid injection cup is in the pre-installed state;

[0068] Figure 3 is Figure 1 exploded view of;

[0069] Figure 4 It is a schematic structural diagram of the third perspective of the liquid injection system of the battery according to an embodiment of the present application, wherein the liquid injection cup is in the pre-installed state;

[0070] Figure 5 is Figure 4 enlarged view of part A in;

[0071] Figure 6 It is a schematic structural diagram of the fourth perspective of the liquid injection system of the battery according to an embodiment of the present application, wherein the liquid injection cup is in the assembled state;

[0072] Figure 7 Schematic flow diagram of the stock solution preparation step according to an embodiment of the present application.

[0073] Description of the reference numerals

[0074] 1. Mounting base; 1a. First support column; 2. Liquid injection module; 21. Tray; 21a. Clearance area; 21b. First support hole; 22. Liquid injection cup; 22a. Pre-installed support part; 22b. Second support hole; 22c. Guide hole; 3. Weighing module; 31. Weighing unit; 311. Weigher; 312. Weighing bracket; 312a. Second support column; 32. Mounting plate; 4. Guide member; 4a. Guide post. Detailed implementation manners

[0075] It should be noted that, without conflict, the embodiments in the present application and the technical features in the embodiments can be combined with each other. The detailed description in the specific implementation manners should be understood as an explanatory illustration of the purpose of the present application and should not be regarded as an improper limitation of the present application.

[0076] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit this application; the terms "including" and "having" and any variations thereof in this application are intended to cover non-exclusive inclusion.

[0077] In the description of the embodiments of the present application, the technical terms "first", "second", "third", etc. are only used to distinguish different objects and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity, specific order or primary-secondary relationship of the indicated technical features. In the description of the embodiments of the present application, "a plurality of" means more than two, unless otherwise specifically defined.

[0078] Referring to "embodiments" herein means that the specific features, structures or characteristics described in connection with the embodiments can be included in at least one embodiment of this application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0079] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the front and rear associated objects.

[0080] In the description of the embodiments of the present application, the orientation or position relationship indicated by technical terms such as "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "circumferential", "height direction", "first direction", and "second direction" are based on the orientation or position relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed, operated or used in a specific orientation. Therefore, they should not be understood as limitations on the embodiments of the present application.

[0081] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, technical terms such as "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, and it can be the internal connection of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0082] In the description of the embodiments of the present application, unless otherwise clearly specified and limited, the technical term "contact" should be understood in a broad sense, and may be direct contact or contact through an intermediate medium layer. It may be contact with essentially no interaction force between the two contacting parties, or it may be contact with interaction force between the two contacting parties.

[0083] With the development of clean energy, more and more devices use electric energy as driving energy, and then power batteries that can store more electric energy and can be charged and discharged repeatedly are developing rapidly, such as lithium-ion batteries. Among them, power batteries are not only used in energy storage power systems such as hydropower, thermal power, wind power and solar power stations, but also widely used in electric vehicles such as electric bicycles, electric motorcycles, electric cars, as well as aerospace and other fields.

[0084] With the country's vigorous promotion of new energy vehicles, new energy vehicles have ushered in a great opportunity for development. The safety and stability of automobiles have always been people's greatest concern. Therefore, improving the safety of new energy vehicles will be one of the important factors that determine whether new energy vehicles can be quickly popularized. Battery modules are the main components of the battery pack of new energy vehicles. Improving the safety of battery modules is an important way to improve the safety of new energy vehicles.

[0085] The battery mentioned in the embodiments of the present application refers to a single physical module including one or more battery cells to provide higher voltage and capacity. For example, the battery mentioned in the present application may include a battery module, a battery pack, etc. Generally, a battery includes a box for encapsulating one or more battery cells. The box can prevent liquids or other foreign objects from affecting the charging or discharging of the battery cells.

[0086] In the present application, the battery cell may include a lithium-ion secondary battery, a lithium-ion primary battery, a lithium-sulfur battery, a sodium-lithium-ion battery, a sodium-ion battery, a magnesium-ion battery, etc., and the embodiments of the present application do not limit this. The battery cell can be in a cylindrical shape, a cuboid shape or other shapes, etc., and the embodiments of the present application do not limit this either.

[0087] The battery cell includes an electrode assembly and an electrolyte. The electrode assembly is composed of a positive electrode sheet, a negative electrode sheet and a separator. The battery cell mainly works by the movement of metal ions between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet includes a positive electrode current collector and a positive electrode active material layer. The positive electrode active material layer is coated on the surface of the positive electrode current collector. The positive electrode current collector without the coated positive electrode active material layer protrudes from the positive electrode current collector with the coated positive electrode active material layer. The positive electrode current collector without the coated positive electrode active material layer serves as the positive electrode tab. Taking a lithium-ion battery as an example, the material of the positive electrode current collector can be aluminum, and the positive electrode active material can be lithium cobaltate, lithium iron phosphate, ternary lithium or lithium manganate, etc. The negative electrode sheet includes a negative electrode current collector and a negative electrode active material layer. The negative electrode active material layer is coated on the surface of the negative electrode current collector. The negative electrode current collector without the coated negative electrode active material layer protrudes from the negative electrode current collector with the coated negative electrode active material layer. The negative electrode current collector without the coated negative electrode active material layer serves as the negative electrode tab. The material of the negative electrode current collector can be copper, and the negative electrode active material can be carbon or silicon, etc. In order to ensure that a large current can pass through without fusing, the number of positive electrode tabs is multiple and stacked together, and the number of negative electrode tabs is multiple and stacked together. The material of the separator can be PP (polypropylene) or PE (polyethylene), etc.

[0088] The battery cell also includes an insulating film and a housing. The insulating film is coated on the outside of the electrode assembly, and the housing encapsulates the electrode assembly coated with the insulating film to form the battery cell. The insulating film can be a mylar film, and the housing can be an aluminum shell. After the electrode assembly is wound and formed, the encapsulation of the mylar film and the housing is completed through the mylar wrapping process and the housing insertion process. Among them, the mylar film plays a role in sealing and protecting the electrode assembly, and the mylar film can effectively insulate the electrode assembly and the housing from each other to avoid internal short circuit of the battery cell. The housing plays a protective role.

[0089] The electrolyte injection process is an important link in the battery manufacturing process, and the injection accuracy is directly related to the cycle performance, safety performance, consistency, etc. of lithium ions.

[0090] In the related art, a liquid storage tank needs to be set up to store the electrolyte transported from the electrolyte room. The liquid injection pump quantitatively pumps the electrolyte in the liquid storage tank into the accommodating device. After the battery is evacuated, the liquid injection valve of the accommodating device is opened, and the electrolyte in the accommodating device is injected into the liquid injection cup. After the electrolyte is injected into the liquid injection cup, the liquid injection valve is closed, and the battery and the liquid injection cup are combined and transported to the next process. It can be seen that each liquid injection cup needs to correspond to a liquid injection pump, and a liquid storage tank and an accommodating device need to be set up to store the electrolyte transported from the electrolyte room, occupying space and increasing the equipment cost. In addition, by using the liquid injection pump to control the injection amount of the electrolyte, the bubbles in the electrolyte will reduce the control accuracy of the electrolyte injection amount, and the electrolyte also needs to be degassed and filtered for impurities, reducing the liquid preparation efficiency.

[0091] In order to improve the liquid preparation efficiency, reduce costs, and reduce the occupied space, please refer to Figures 1 to 6 In an embodiment of the present application, a liquid injection system for a battery is provided. The liquid injection system includes a mounting base 1, a liquid injection module 2, and a weighing module 3. The liquid injection module 2 includes a tray 21 and a liquid injection cup 22. The weighing module 3 is arranged on the mounting base 1. Among them, the liquid injection cup 22 includes a pre-installed state and an assembled state. When the liquid injection cup 22 is in the pre-installed state, the liquid injection cup 22 is pre-installed on the tray 21. The weight of the liquid injection cup 22 is borne by the tray 21. When the liquid injection cup 22 is in the assembled state, the liquid injection cup 22 is assembled onto the weighing module 3. The weight of the liquid injection cup 22 is borne by the weighing module 3. The weighing module 3 is used to weigh the liquid injection cup 22.

[0092] The specific structure of the mounting base 1 is not limited here. The mounting base 1 is the main support structure for supporting and installing the liquid injection module 2 and the weighing module 3.

[0093] Exemplarily, the mounting base 1 is a marble platform. By setting the mounting base 1 as a marble platform, it has a good vibration damping effect, avoids the influence of environmental vibration on the liquid injection system, and improves the reliability of the liquid injection system.

[0094] The weighing module 3 is arranged on the mounting base 1 and corresponds to the liquid injection cup 22 one by one, and is used to weigh the liquid injection cup 22. That is to say, the weighing module 3 can weigh the liquid injection cup 22 in real time to obtain the injection amount of the electrolyte in the liquid injection cup 22.

[0095] The liquid injection module 2 is used to inject liquid into the battery.

[0096] The liquid injection module 2 includes a tray 21 and a liquid injection cup 22, and the tray 21 is used to carry the liquid injection cup 22.

[0097] It should be noted that the number of the liquid injection cups 22 is not limited here. For example, it can be one or multiple.

[0098] In the embodiments of the present application, "a plurality of" means two or more in number.

[0099] Exemplarily, the number of the liquid injection cups 22 is a plurality. When the liquid injection cups 22 are in the pre-installed state, the plurality of liquid injection cups 22 are carried on the tray 21.

[0100] When the liquid injection cups 22 are in the pre-installed state, the liquid injection cups 22 are pre-installed on the tray 21, and the weight of the liquid injection cups 22 is borne by the tray 21. At this time, the liquid injection module 2 is not assembled to the mounting seat 1. By arranging all the liquid injection cups 22 on the tray 21, it is convenient to transfer the liquid injection cups 22.

[0101] After the liquid injection module 2 is assembled to the mounting seat 1, the liquid injection cups 22 are switched from the pre-installed state to the assembled state. At this time, the liquid injection cups 22 are assembled to the weighing module 3, and the weight of the liquid injection cups 22 is borne by the weighing module 3. The weighing module 3 is used to weigh the liquid injection cups 22. Thus, the initial weight of the liquid injection cups 22 (the initial weight refers to the weight when no electrolyte has been injected, that is, the weight of the liquid injection cups 22 themselves) can be weighed by the weighing module 3. After the liquid injection device injects electrolyte into the liquid injection cups 22, the real-time weight of the liquid injection cups 22 (the real-time weight refers to the weight after the electrolyte is injected into the liquid injection cups 22, that is, the weight of the liquid injection cups 22 themselves and the weight of the electrolyte) is weighed by the weighing module 3, so as to obtain the weight of the electrolyte injected into the liquid injection cups 22.

[0102] It can be understood that by weighing the weight of the electrolyte by the weighing module 3 to control the liquid injection amount, there is no need to control the liquid injection amount through a liquid injection pump, so there is no need for a defoaming action, which improves the liquid preparation efficiency. And because there is no need for a defoaming action, the electrolyte in the electrolyte chamber can be directly injected into the liquid injection cups 22 after being filtered by a filter, and is controlled by a liquid injection valve (a liquid injection valve is arranged on the electrolyte conveying pipeline to control the on-off of the electrolyte), which simplifies the original liquid injection station structure (liquid injection pump, accommodating device, pipeline and valve body), reduces the occupied space, reduces the equipment cost, shrinks the equipment size, and simplifies the equipment pipeline structure.

[0103] Exemplarily, the liquid injection system includes a valve opening device, and the valve opening device includes an open state and a closed state. This valve opening device is a normally closed valve opening device. In this way, electrolyte can be injected into the liquid injection cups 22 in advance at any time before the battery is combined with the liquid injection cups 22, which can reduce the serial time (liquid preparation time) and improve the production efficiency and production rhythm. That is to say, before the normally closed valve opening device is unlocked, the liquid injection cups 22 are relatively sealed with the outside world, ensuring that the electrolyte does not leak during liquid injection weighing. At the same time, the liquid injection weighing action can be completed when the battery is grouped, improving the production rhythm.

[0104] The liquid injection system of the battery provided by the embodiment of the present application, the liquid injection system includes a mounting base 1, a liquid injection module 2 and a weighing module 3. The liquid injection cup 22 includes a pre-installed state and an assembled state. When the liquid injection cup 22 is in the pre-installed state, the liquid injection cup 22 is pre-installed on the tray 21. At this time, the weight of the liquid injection cup 22 is borne by the tray 21. When the liquid injection cup 22 is in the assembled state, the liquid injection cup 22 is assembled onto the weighing module 3. At this time, the weight of the liquid injection cup 22 is borne by the weighing module 3, and the weighing module 3 is used to weigh the liquid injection cup 22. That is to say, by setting the weighing module 3 to weigh the liquid injection cup 22, that is, the weighing module 3 can weigh the liquid injection cup 22 in real time to obtain the amount of electrolyte injected into the liquid injection cup 22. There is no need for a liquid injection pump to control the liquid injection volume, and there is no need for a defoaming operation, thus improving the liquid preparation efficiency. In addition, the electrolyte in the electrolyte chamber can be directly injected into the liquid injection cup 22 after being filtered by a filter, simplifying the structure, reducing the cost, reducing the occupied space, and improving the structural compactness of the liquid injection system.

[0105] In addition, since the real-time weight A2 of the liquid injection cup 22 can be obtained through the weighing module 3 after the liquid injection cup 22 is filled with liquid (A2 refers to the weight after the electrolyte is injected into the liquid injection cup 22, that is, the weight of the liquid injection cup 22 itself and the weight of the electrolyte), after the electrolyte in the liquid injection cup 22 is injected into the battery, the liquid injection cup 22 is weighed at this time to obtain A3 (A3 refers to the weight of the liquid injection cup 22 itself and the weight of the remaining electrolyte), that is, the weight of the electrolyte injected into the battery is A2 - A3. That is to say, by adopting the liquid injection method of the embodiment of the present application, the process of separately weighing before and after battery liquid injection can be cancelled, and the production efficiency can be improved.

[0106] In some embodiments, please refer to Figures 1 to 6 , the tray 21 includes at least one pre-installed support position, and the liquid injection cup 22 includes at least one pre-installed support portion 22a. When the liquid injection cup 22 is in the pre-installed state, the liquid injection cup 22 is supported on the pre-installed support position through the pre-installed support portion 22a and is located at a first height relative to the tray 21.

[0107] The tray 21 includes at least one pre-installed support position means that the number of pre-installed support positions can be one or more.

[0108] The liquid injection cup 22 includes at least one pre-installed support portion 22a means that the number of pre-installed support portions 22a can be one or more.

[0109] That is to say, by setting at least one pre-installed support position on the tray 21 and at least one pre-installed support portion 22a on the liquid injection cup 22, when the liquid injection cup 22 is in the pre-installed state, the liquid injection cup 22 is supported on the pre-installed support position through the pre-installed support portion 22a to realize the pre-installation of the liquid injection cup 22.

[0110] In some embodiments, please continue to refer to Figures 1 to 6 , the weighing module 3 includes at least one assembly support position, and the liquid injection cup 22 includes at least one assembly support portion. When the liquid injection cup 22 is in the assembled state, the liquid injection cup 22 is supported on the first assembly support position through the assembly support portion and is located at a second height relative to the tray 21. The second height is not equal to the first height.

[0111] The weighing module 3 includes at least one assembly support position means that the number of assembly support positions can be one or more.

[0112] The liquid injection cup 22 includes at least one assembly support portion means that the number of assembly support portions can be one or more.

[0113] That is to say, by setting at least one assembly support position on the weighing module 3 and at least one assembly support portion on the liquid injection cup 22, when the liquid injection cup 22 is in the assembled state, the liquid injection cup 22 is supported on the assembly support position through the assembly support portion to achieve the assembly of the liquid injection cup 22.

[0114] The second height is not equal to the first height, that is to say, the height of the liquid injection cup 22 relative to the tray 21 is different in the pre-assembled state and the assembled state. In this way, it helps to realize the switching of the liquid injection cup 22 between the pre-assembled state and the assembled state.

[0115] In some embodiments, please refer to Figure 3 , the tray 21 is provided with a clearance area 21a, and the liquid injection cup 22 passes through the clearance area 21a through the weighing module 3.

[0116] The specific structural form of the clearance area 21a is not limited here as long as the liquid injection cup 22 can pass through the clearance area 21a.

[0117] By providing the clearance area 21a on the tray 21, in the pre-assembled state of the liquid injection cup 22, the liquid injection cup 22 passes through the clearance area 21a and is supported on the pre-assembled support position through the pre-assembled support portion 22a to achieve the pre-assembly of the liquid injection cup 22. When the liquid injection cup 22 is in the assembled state, the liquid injection cup 22 is supported on the assembly support position through the assembly support portion to achieve the assembly of the liquid injection cup 22. For example, the assembly support position cooperates with the assembly support portion to lift the liquid injection cup 22 so that the pre-assembled support portion 22a is separated from the pre-assembled support position, so that the weight of the liquid injection cup 22 is borne by the weighing module 3.

[0118] In some embodiments, please refer to Figure 1 and Figure 3 , at least one first support column 1a is provided on the mounting base 1, at least one first support hole 21b is provided on the tray 21, and the tray 21 is supported on the first support column 1a through the first support hole 21b.

[0119] The statement that at least one first support column 1a is provided on the mounting base 1 means that the number of the first support columns 1a can be one or more than one.

[0120] Specifically, the mounting base 1 is a rectangular marble platform. The number of the first support columns 1a is four, which are respectively arranged at four top corners of the marble platform, so as to improve the support reliability of the mounting base 1.

[0121] The statement that the tray 21 is provided with at least one first support hole 21b means that the number of the first support holes 21b can be one or more than one.

[0122] Specifically, the tray 21 is also rectangular. The number of the first support holes 21b is four, which are respectively arranged at four top corners of the tray 21 and correspond to the first support columns 1a on the tray 21, so as to improve the reliability of the connection structure between the mounting base 1 and the tray 21.

[0123] That is to say, the mounting base 1 is provided with at least one first support column 1a, the tray 21 is provided with at least one first support hole 21b, and the first support hole 21b cooperates with the first support column 1a, so that the mounting base 1 supports the tray 21, and the connection structure is simple and reliable.

[0124] It should be noted that the specific structures of the pre-installed support part 22a and the pre-installed support position are not limited herein.

[0125] In some embodiments, please refer to Figure 3 and Figure 5 , at least part of the outer side wall of the liquid injection cup 22 is convexly provided with a pre-installed support part 22a. When the liquid injection cup 22 is in a pre-installed state, the liquid injection cup 22 is supported on the upper surface of the tray 21 through the pre-installed support part 22a and is located at a first height relative to the tray 21.

[0126] The statement that at least part of the outer side wall of the liquid injection cup 22 is convexly provided with a pre-installed support part 22a means that it can be that part of the outer side wall of the liquid injection cup 22 is convexly provided with a pre-installed support part 22a, as long as the liquid injection cup 22 can be supported on the upper surface of the tray 21 through the pre-installed support part 22a on the outer side wall, or it can also be that the entire outer side wall of the liquid injection cup 22 is convexly provided with a pre-installed support part 22a, that is, a pre-installed support part 22a is provided in a ring shape on the outer side wall of the liquid injection cup 22.

[0127] The liquid injection cup 22 is supported on the upper surface of the tray 21 through the pre-installed support part 22a, that is, the liquid injection cup 22 is supported on the edge of the clearance area 21a of the tray 21 through the pre-installed support part 22a.

[0128] By protruding at least a part of the outer wall of the liquid injection cup 22 with a pre-installation support portion 22a, when the liquid injection cup 22 is in the pre-installation state, the liquid injection cup 22 is supported on the upper surface of the tray 21 through the pre-installation support portion 22a. This connection structure is simple and reliable, which is beneficial to pre-install the liquid injection cup 22 on the tray 21 and is also beneficial to the switching of the liquid injection cup 22 between the pre-installation state and the assembly state.

[0129] In some embodiments, please refer to Figures 3 to 6 , at least one second support hole 22b is provided at the bottom of the liquid injection cup 22. The weighing module 3 is disposed below the tray 21 and includes at least one second support post 312a. When the liquid injection cup 22 is in the assembly state, the pre-installation support portion 22a is spaced apart from the upper surface of the tray 21. The liquid injection cup 22 is supported on the second support post 312a through the second support hole 22b and is located at a second height relative to the tray 21. The second height is not equal to the first height.

[0130] The statement that at least one second support hole 22b is provided at the bottom of the liquid injection cup 22 means that the number of the second support holes 22b can be one or more.

[0131] The weighing module 3 is disposed below the tray 21, that is to say, the weighing module 3 is disposed between the tray 21 and the mounting base 1, which is beneficial to weighing the weight of the liquid injection cup 22.

[0132] The statement that the weighing module 3 includes at least one second support post 312a means that the number of the second support posts 312a can be one or more.

[0133] By providing at least one second support hole 22b at the bottom of the liquid injection cup 22 and at least one second support post 312a on the weighing module 3. When the liquid injection cup 22 is in the pre-installation state, the liquid injection cup 22 is supported on the upper surface of the tray 21 through the pre-installation support portion 22a. During the process of assembling the liquid injection module 2 onto the mounting base 1, the second support post 312a on the weighing module 3 contacts the second support hole 22b at the bottom of the liquid injection cup 22 and gradually jacks up the liquid injection cup 22, so that the pre-installation support portion 22a of the liquid injection cup 22 gradually moves away from the upper surface of the tray 21. When the tray 21 is completely supported on the mounting base 1, the weighing module 3 completely jacks up the liquid injection cup 22, and the liquid injection cup 22 is separated from contact with the tray 21, that is, the pre-installation support portion 22a is spaced apart from the upper surface of the tray 21, so as to realize the switching of the liquid injection cup 22 from the pre-installation state pre-installed on the tray 21 to the assembly state assembled on the weighing module 3. At this time, the liquid injection cup 22 is located at a second height relative to the tray 21.

[0134] It should be noted that the specific structure of the weighing module 3 is not limited herein as long as it can weigh the liquid injection cup 22.

[0135] In some embodiments, refer to Figures 3 to 4 , the weighing module 3 includes a weigher 311 and a weighing bracket 312 disposed on the weigher 311. A second support column 312a is disposed on the weighing bracket 312. The weigher 311 is used to weigh the liquid injection cup 22.

[0136] The specific type of the weigher 311 is not limited herein, as long as it can weigh the liquid injection cup 22. Exemplarily, the weigher 311 is an electronic scale.

[0137] That is to say, by setting the weighing module 3 to include a weigher 311 and a weighing bracket 312, the weighing bracket 312 is disposed on the weigher 311, and the weighing bracket 312 is provided with a second support column 312a for contacting the second support hole 22b at the bottom of the liquid injection cup 22 to achieve the support of the liquid injection cup 22, while the weigher 311 is located below the weighing bracket 312. Thus, when the weighing bracket 312 jacks up and supports the liquid injection cup 22 below the liquid injection cup 22, the weigher 311 can weigh the liquid injection cup 22.

[0138] In some embodiments, refer to Figures 3 to 4 , the weighing module 3 further includes a mounting plate 32, and the weigher 311 is disposed on the mounting plate 32.

[0139] By providing the mounting plate 32 and disposing the weigher 311 on the mounting plate 32, and assembling the mounting plate 32 to the mounting seat 1, it is beneficial to the assembly of the weigher 311.

[0140] In some embodiments, refer to Figures 2 to 4 , the weighing module 3 includes a plurality of weighing units 31. Each weighing unit 31 includes a weigher 311 and a weighing bracket 312. The liquid injection module 2 includes a plurality of liquid injection cups 22, and the liquid injection cups 22 correspond to the weighing units 31 one by one.

[0141] The weighing module 3 including a plurality of weighing units 31 is beneficial to simultaneously weighing each liquid injection cup 22.

[0142] The number of the weighing units 31 corresponds to the number of the liquid injection cups 22, that is, the liquid injection cups 22 and the weighing units 31 correspond to each other one by one.

[0143] By setting the weighing module 3 to include a plurality of weighing units 31, and the weighing units 31 corresponding to the liquid injection cups 22 one by one, the simultaneous weighing of a plurality of liquid injection cups 22 respectively is realized, improving the effect of preparing the liquid.

[0144] In some embodiments, refer to Figures 2 to 4 , the liquid injection module 2 further includes a guide member 4 disposed on the tray 21. It is used to guide the movement of the liquid injection cup 22 in its height direction.

[0145] It is understandable that when the liquid injection cup 22 is switched from the pre-installed state pre-installed on the tray 21 to the assembled state assembled on the weighing module 3, the liquid injection cup 22 moves along its height direction. By providing the guiding member 4 to guide the movement of the liquid injection cup 22 along its height direction, it is possible to prevent the liquid injection cup 22 from shifting during the lifting process and improve the reliability of the movement process of the liquid injection cup 22.

[0146] It should be noted that the specific structure of the guiding member 4 is not limited herein.

[0147] In some embodiments, please continue to refer to Figures 2 to 4 , the guiding member 4 is a guiding bracket. A guiding groove is defined between the upper surface of the guiding bracket and the upper surface of the tray 21. The top wall of the guiding groove is provided with a guiding post 4a extending towards the upper surface of the tray 21. A guiding hole 22c is provided on the pre-installed supporting portion 22a, and the guiding post 4a is slidably engaged with the guiding hole 22c to guide the movement of the liquid injection cup 22 along its height direction.

[0148] A guiding groove is defined between the upper surface of the guiding bracket and the upper surface of the tray 21. The pre-installed supporting portion 22a of the liquid injection cup 22 is disposed in the guiding groove and moves within the guiding groove. In this way, the guiding bracket can limit the liquid injection cup 22 and can, to a certain extent, prevent the liquid injection cup 22 from completely detaching from the tray 21.

[0149] The top wall of the guiding groove is provided with a guiding post 4a extending towards the upper surface of the tray 21, that is to say, the guiding post 4a extends along the height direction of the liquid injection cup 22.

[0150] A guiding hole 22c is provided on the pre-installed supporting portion 22a, and the guiding post 4a is slidably engaged with the guiding hole 22c, that is to say, the guiding bracket guides the pre-installed supporting portion 22a to realize the guiding of the liquid injection cup 22.

[0151] The number of guiding brackets is not limited herein. The number of guiding brackets can be one or multiple. Exemplarily, the number of guiding brackets is two, and the two guiding brackets are respectively located on both sides of the liquid injection cup 22 along the width direction.

[0152] By providing a guiding bracket having a guiding post 4a and providing a guiding hole 22c on the pre-installed supporting portion 22a so that the guiding post 4a is slidably engaged with the guiding hole 22c to guide the movement of the liquid injection cup 22 along its height direction, it is possible to prevent the liquid injection cup 22 from shifting during the lifting process. In addition, the guiding bracket can also limit the liquid injection cup 22 and can, to a certain extent, prevent the liquid injection cup 22 from completely detaching from the tray 21.

[0153] The second aspect of the embodiments of the present application further provides a liquid injection method for a battery, which is applied to the liquid injection system of the battery in any embodiment of the present application. The liquid injection module 2 further includes a liquid injection device and a valve opening device provided on the liquid injection cup 22. The valve opening device has an open state and a closed state.

[0154] The liquid injection method includes a liquid preparation step. Please refer to Figure 7 , and the liquid preparation step includes:

[0155] Step S100: Obtain the initial weight A1 of the liquid injection cup through the weighing module;

[0156] Step S200: Open the liquid injection valve of the liquid injection device and inject electrolyte into the liquid injection cup;

[0157] Step S300: Obtain the real-time weight A2 of the liquid injection cup through the weighing module;

[0158] Step S400: Confirm whether the liquid preparation requirement is met by comparing the size of A2 - A1 with the target weight A0;

[0159] Step S500: If the liquid preparation requirement is met, the liquid preparation is completed.

[0160] It should be noted that the liquid preparation step refers to injecting electrolyte into the liquid injection cup 22 for standby.

[0161] Exemplarily, the liquid injection system includes a valve opening device provided on the liquid injection cup 22, and the valve opening device is provided at the bottom of the liquid injection cup 22.

[0162] The valve opening device includes an open state and a closed state. When the valve opening device is in the open state, the bottom of the liquid injection cup 22 can be communicated with the outside through the valve opening device. When the valve opening device is in the closed state, the bottom of the liquid injection cup 22 is not communicated with the outside. That is to say, this valve opening device is a normally closed valve opening device. In this way, electrolyte can be injected into the liquid injection cup 22 in advance at any time before the battery and the liquid injection cup 22 are combined, which can reduce the serial time (liquid preparation time) and improve the production efficiency and production rhythm. That is to say, before the normally closed valve opening device is unlocked, the liquid injection cup 22 is relatively sealed with the outside world, ensuring that the electrolyte does not leak during liquid injection weighing. At the same time, the liquid injection weighing action can be completed when the battery is grouped, improving the production rhythm.

[0163] The liquid injection system of the battery provided by the embodiment of the present application includes a mounting base 1, a liquid injection module 2, and a weighing module 3. The liquid injection module 2 includes a tray 21 and a liquid injection cup 22. The weighing module 3 is disposed on the mounting base 1. Among them, the liquid injection cup 22 includes a pre-installed state and an assembled state. When the liquid injection cup 22 is in the pre-installed state, the liquid injection cup 22 is pre-installed on the tray 21. The weight of the liquid injection cup 22 is borne by the tray 21. When the liquid injection cup 22 is in the assembled state, the liquid injection cup 22 is assembled onto the weighing module 3. The weight of the liquid injection cup 22 is borne by the weighing module 3. The weighing module 3 is used to weigh the liquid injection cup 22.

[0164] When the liquid injection cup 22 is in the pre-installed state, the liquid injection cup 22 is pre-installed on the tray 21, and the weight of the liquid injection cup 22 is borne by the tray 21. At this time, the liquid injection module 2 is not assembled to the mounting base 1. By setting all the liquid injection cups 22 on the tray 21, it is convenient to transfer the liquid injection cups 22.

[0165] After the liquid injection module 2 is assembled to the mounting base 1, the liquid injection cup 22 switches from the pre-installed state to the assembled state. At this time, the liquid injection cup 22 is assembled onto the weighing module 3, and the weight of the liquid injection cup 22 is borne by the weighing module 3. The weighing module 3 is used to weigh the liquid injection cup 22. Thus, the initial weight of the liquid injection cup 22 (the initial weight refers to the weight before the electrolyte is injected, that is, the weight of the liquid injection cup 22 itself) can be weighed by the weighing module 3. After the liquid injection device injects the electrolyte into the liquid injection cup 22, the real-time weight of the liquid injection cup 22 (the real-time weight refers to the weight after the electrolyte is injected into the liquid injection cup 22, that is, the weight of the liquid injection cup 22 itself and the weight of the electrolyte) is weighed by the weighing module 3, so as to obtain the weight of the electrolyte injected into the liquid injection cup 22.

[0166] It can be understood that by weighing the weight of the electrolyte by the weighing module 3 to control the liquid injection volume, there is no need to control the liquid injection volume through a liquid injection pump, so there is no need for a defoaming operation, which improves the liquid preparation efficiency. And because there is no need for a defoaming operation, the electrolyte in the electrolyte room can be directly injected into the liquid injection cup 22 after being filtered by a filter, and is controlled by a liquid injection valve, which simplifies the original liquid injection station structure (liquid injection pump, accommodating device, pipeline, and valve body) and reduces the occupied space.

[0167] During the process of preparing the liquid in the liquid injection cup 22, first, the weighing module 3 and the liquid injection module 2 are assembled onto the mounting base 1. The liquid injection cup 22 is switched from the pre-installed state to the assembled state, and the weight of the liquid injection cup 22 is borne by the weighing module 3. The weighing module 3 is used to weigh the liquid injection cup 22. The weighing module 3 obtains the initial weight A1 of each liquid injection cup 22 (that is, the weight of each liquid injection cup 22 before injecting liquid). After weighing, the system records the initial weight A1 of each liquid injection cup 22, opens the liquid injection valve of the liquid injection device, and injects electrolyte into the liquid injection cup 22. The real-time weight A2 of the liquid injection cup 22 is obtained through the weighing module 3. The system determines whether the liquid preparation requirement is met by comparing the size of A2 - A1 with the target weight A0. If the liquid preparation requirement is met, the liquid preparation is completed. That is to say, by setting the weighing module 3 to weigh the liquid injection cup 22, the injection amount of the electrolyte in the liquid injection cup 22 can be judged, without the need for a liquid injection pump to control the injection amount, and there is no need for a defoaming operation either, thus improving the liquid preparation efficiency. In addition, after the electrolyte in the electrolyte chamber is filtered by the filter, it can be directly injected into the liquid injection cup 22, simplifying the structure, reducing the cost, reducing the occupied space, and improving the structural compactness of the liquid injection system. The liquid preparation steps of this liquid injection method are highly efficient. Before the normally closed valve opening device is unlocked, the liquid injection cup 22 is relatively sealed from the outside, ensuring that the electrolyte does not leak during liquid injection and weighing. At the same time, the liquid injection and weighing operations can be completed during the battery pack tray, improving the production beat.

[0168] In addition, since the real-time weight A2 of the liquid injection cup 22 can be obtained through the weighing module 3 after the liquid injection cup 22 finishes injecting liquid (A2 refers to the weight after injecting electrolyte into the liquid injection cup 22, that is, the weight of the liquid injection cup 22 itself and the electrolyte), after injecting the electrolyte in the liquid injection cup 22 into the battery and weighing the liquid injection cup 22 at this time to obtain A3 (A3 refers to the weight of the liquid injection cup 22 itself and the remaining electrolyte), that is, the weight of the electrolyte injected into the battery is A2 - A3. That is to say, by adopting the liquid injection method of the embodiment of the present application, the process of separately weighing before and after battery liquid injection can be cancelled, improving the production efficiency.

[0169] In some embodiments, determining whether the liquid preparation requirement is met by comparing the size of A2 - A1 with the target weight A0 includes:

[0170] Step S410: If A2 - A1 ≥ A0, it is determined that the liquid preparation requirement is met;

[0171] Step S420: If A2 - A1 < A0, it is determined that the liquid preparation requirement is not met, and continue to inject electrolyte into the liquid injection cup 22.

[0172] A2 - A1 refers to the weight of the electrolyte injected into the liquid injection cup 22, and the target weight A0 is greater than or equal to the weight of the electrolyte that the battery needs to inject.

[0173] That is to say, if the weight of the electrolyte injected into the liquid injection cup 22, A2 - A1, is greater than or equal to the target weight A0, that is, the electrolyte stored in the liquid injection cup 22 is sufficient to meet the amount of electrolyte required to be injected into the battery, it indicates that the liquid preparation requirement is met at this time. On the contrary, if the weight of the electrolyte injected into the liquid injection cup 22, A2 - A1, is less than the target weight A0, that is, the electrolyte stored in the liquid injection cup 22 does not meet the amount of electrolyte required to be injected into the battery, it indicates that the liquid preparation requirement is not met at this time, and the electrolyte continues to be injected into the liquid injection cup 22 until the liquid preparation requirement is met.

[0174] In some embodiments, if A2 - A1 < A0, it is confirmed that the liquid preparation requirement is not met, and the electrolyte continues to be injected into the liquid injection cup 22. It further includes: if the liquid preparation requirement is still not met within a predetermined time, the system gives an alarm prompt.

[0175] If the electrolyte injection standard is not reached within a predetermined time, that is, the liquid preparation requirement is not met within the predetermined time, at this time, it represents that there may be a problem with the system, and the system gives an alarm prompt so that the staff can come for maintenance in time to avoid wasting time.

[0176] In some embodiments, if A2 - A1 ≥ A0, it is confirmed that the liquid preparation requirement is met, including:

[0177] Based on the electrolyte flow rate q of the liquid injection device and the response time t of the injection valve, it is determined whether to close the injection valve.

[0178] It can be understood that the injection valve has a certain response time, that is, when the system issues an instruction to close the injection valve, the injection valve needs to close after a certain time. During the response time, a part of the electrolyte will continue to flow into the liquid injection cup 22, resulting in inaccurate liquid preparation.

[0179] Therefore, in the embodiment of the present application, based on the electrolyte flow rate q of the liquid injection device and the response time t of the injection valve, it is determined whether to close the injection valve, that is, the injection amount of the electrolyte during the response time of the injection valve is calculated, and the injection valve is closed in advance, thereby improving the accuracy of liquid preparation.

[0180] In some embodiments, based on the electrolyte flow rate q of the liquid injection device and the response time t of the injection valve, determining whether to close the injection valve includes:

[0181] If A2 - A1 + qt ≥ A0, close the injection valve;

[0182] If A2 - A1 + qt < A0, open the injection valve and continue to inject the electrolyte into the liquid injection cup 22.

[0183] The electrolyte flow rate q of the liquid injection device is obtained through experiments, and the reaction time t of the liquid injection valve is measured simultaneously. Calculate the injection volume of the electrolyte within the closing reaction time t of the liquid injection valve at the normal flow rate, which is qt. That is, the corrected target injection volume is the original target injection volume minus the injection volume of the electrolyte within the closing reaction time t of the liquid injection valve, i.e., A2 - A1 + qt ≥ A0. If A2 - A1 + qt < A0, it indicates that the liquid preparation requirement is not met at this time. Then, the liquid injection valve is opened, and electrolyte is continuously injected into the liquid injection cup 22 until the liquid preparation requirement is met, thereby improving the accuracy of liquid preparation.

[0184] In some embodiments, the battery includes a switching valve having an open state and a closed state. The liquid injection system further includes a vacuum pumping module independent of the liquid injection module 2. The liquid injection method further includes a vacuum pumping step, and the liquid preparation step is before the vacuum pumping step or is carried out simultaneously with the vacuum pumping step. The vacuum pumping step includes:

[0185] Dock the vacuum pumping pipeline of the vacuum pumping module with the switching valve to make the switching valve in the open state;

[0186] Control the vacuum pumping device of the vacuum pumping module to pump the battery;

[0187] After confirming that the vacuum pumping is completed, separate the vacuum pumping pipeline from the switching valve to make the switching valve in the closed state.

[0188] The battery includes a switching valve having an open state and a closed state. That is to say, the switching valve is normally closed. When the switching valve is not affected by external forces, the internal cavity of the battery is kept relatively sealed from the external environment.

[0189] The liquid injection system further includes a vacuum pumping module independent of the liquid injection module 2. In this way, the vacuum pumping pipeline of the vacuum pumping module and the liquid injection pipeline of the liquid injection module 2 do not need to be shared, avoiding the situation that the residual electrolyte in the pipeline diffuses to other pipelines and valve bodies of the vacuum pumping module during the vacuum pumping process, resulting in blockage of the pipelines and valve bodies.

[0190] The liquid injection method further includes a vacuum pumping step, and the liquid preparation step is before the vacuum pumping step or is carried out simultaneously with the vacuum pumping step. Since both the switching valve of the battery and the valve opening device of the liquid injection system are normally closed, electrolyte can be injected into the liquid injection cup 22 in advance at any time before the combination of the battery and the liquid injection cup 22, reducing the serial time (liquid preparation time) to improve production efficiency.

[0191] The vacuum pumping device is, for example, a vacuum pump.

[0192] It should be noted that after a single battery pack tray is completed, the handling robot can then pump the battery packs in the tray, or a single battery can be pumped and then tray assembled.

[0193] When evacuating, by docking the evacuation pipeline of the evacuation module with the switching valve to keep the switching valve in the open state, controlling the evacuation device of the evacuation module to evacuate the battery, after confirming the completion of evacuation, separating the evacuation pipeline from the switching valve to keep the switching valve in the closed state. At this time, the evacuation step is completed. The liquid injection system further includes an evacuation module independent of the liquid injection module 2. In this way, there is no need to share the evacuation pipeline of the evacuation module and the liquid injection pipeline of the liquid injection module 2, avoiding the diffusion of residual electrolyte in the pipeline to other pipelines and valve bodies of the evacuation module during evacuation, resulting in blockage of the pipelines and valve bodies. And the liquid preparation step is before the evacuation step, or is carried out simultaneously with the evacuation step. In this way, the electrolyte can be injected into the liquid injection cup 22 in advance at any time before the battery is combined with the liquid injection cup 22, reducing the serial time (liquid preparation time) to improve production efficiency.

[0194] In some embodiments, the liquid injection method further includes a liquid injection step after the evacuation step and the liquid preparation step. The liquid injection step includes:

[0195] Docking the valve opening device with the switching valve to keep both the valve opening device and the switching valve in the open state;

[0196] Controlling the liquid injection module 2 to inject liquid into the battery;

[0197] After confirming the completion of liquid injection, separating the valve opening device from the switching valve to keep both the valve opening device and the switching valve in the closed state.

[0198] The evacuation step can be completed at any stage before battery liquid injection.

[0199] When injecting liquid, the lifting system brings the valve opening device of the liquid injection cup 22 into contact with the switching valve of the battery (for example, controlling the tray 21 of the liquid injection cup 22 to move towards the battery, or controlling the tray 21 of the battery to move towards the liquid injection cup 22). First, the valve opening device of the liquid injection cup 22 contacts the switching valve of the battery. After contact, the formed liquid injection channel is kept sealed from the external environment. Due to the mutual acting force on the valve opening device and the switching valve, the switching valve is forced to open, and at the same time, the valve opening device is also opened by the mutual acting force. At this time, both the valve opening device and the switching valve are in the open state, and the liquid injection module 2 is controlled to inject liquid into the battery. After confirming the completion of liquid injection, the valve opening device is separated from the switching valve to keep both the valve opening device and the switching valve in the closed state.

[0200] In some embodiments, the opening pressure of the valve opening device is greater than or equal to the opening pressure of the switching valve.

[0201] The opening pressure of the valve opening device is greater than that of the switching valve. That is to say, after the valve opening device abuts against the battery, due to the interaction force between the valve opening device and the switching valve, the switching valve opens first and the valve opening device opens later. In this way, during the liquid injection process, it is possible to avoid the situation where the switching valve of the battery is still in the closed state after the valve opening device is opened, thereby improving the problem of electrolyte leakage.

[0202] The opening pressure of the valve opening device is equal to that of the switching valve. That is to say, after the valve opening device abuts against the battery, due to the interaction force between the valve opening device and the switching valve, the switching valve and the valve opening device open simultaneously. In this way, during the liquid injection process, it is possible to avoid the situation where the switching valve of the battery is still in the closed state after the valve opening device is opened, thereby improving the problem of electrolyte leakage.

[0203] By setting the opening pressure of the valve opening device to be greater than or equal to that of the switching valve, it is possible to avoid the situation where the switching valve of the battery is still in the closed state after the valve opening device is opened, thereby improving the problem of electrolyte leakage.

[0204] In the description of the present application, the descriptions with reference to terms such as "in one embodiment", "in some embodiments", "in other embodiments", "in still other embodiments", or "exemplary" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the present application. In the present application, the schematic expressions of the above terms are not necessarily directed to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine different embodiments or examples described in the present application and the features of different embodiments or examples.

[0205] The above are only the preferred embodiments of the present application and are not used to limit the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application are included in the protection scope of the present application.

Claims

1. A liquid injection system for a battery, characterized in that, Comprising: Mounting base; Liquid injection module, including a tray and a liquid injection cup; Weighing module, disposed on the mounting base; Wherein, the liquid injection cup includes a pre-installed state and an assembled state. In the pre-installed state of the liquid injection cup, the liquid injection cup is pre-installed on the tray, and the weight of the liquid injection cup is borne by the tray; in the assembled state of the liquid injection cup, the liquid injection cup is assembled onto the weighing module, and the weight of the liquid injection cup is borne by the weighing module, and the weighing module is used to weigh the liquid injection cup.

2. The liquid injection system according to claim 1, characterized in that, The tray includes at least one pre-installed support position, and the liquid injection cup includes at least one pre-installed support portion. In the pre-installed state of the liquid injection cup, the liquid injection cup is supported on the pre-installed support position through the pre-installed support portion and is located at a first height relative to the tray.

3. The liquid injection system according to claim 2, wherein, The weighing module includes at least one assembled support position, and the liquid injection cup includes at least one assembled support portion. In the assembled state of the liquid injection cup, the liquid injection cup is supported on the first assembled support position through the assembled support portion and is located at a second height relative to the tray, and the second height is not equal to the first height.

4. The liquid injection system according to any one of claims 1-3, characterized in that, The tray is provided with a clearance area, and the liquid injection cup passes through the clearance area through the weighing module.

5. The liquid injection system according to any one of claims 1-3, characterized in that At least one first support column is provided on the mounting base, and at least one first support hole is provided on the tray, and the tray is supported on the first support column through the first support hole.

6. The liquid injection system according to claim 1, wherein At least a part of the outer side wall of the liquid injection cup protrudes with a pre-installed support portion. In the pre-installed state of the liquid injection cup, the liquid injection cup is supported on the upper surface of the tray through the pre-installed support portion and is located at a first height relative to the tray.

7. The liquid injection system according to claim 6, characterized in that, At least one second support hole is provided at the bottom of the liquid injection cup. The weighing module is disposed below the tray and includes at least one second support column; in the assembled state of the liquid injection cup, the pre-installed support portion is spaced from the upper surface of the tray, and the liquid injection cup is supported on the second support column through the second support hole and is located at a second height relative to the tray, and the second height is not equal to the first height.

8. The liquid injection system according to claim 7, wherein, The weighing module includes a weighing device and a weighing bracket disposed on the weighing device, the second support column is disposed on the weighing bracket, and the weighing device is used to weigh the liquid injection cup.

9. The liquid injection system according to claim 8, wherein The weighing module further includes a mounting plate, and the weighing device is disposed on the mounting plate.

10. The liquid injection system according to claim 7, characterized in that, The weighing module includes a plurality of weighing units, each of the weighing units includes the weighing device and the weighing bracket, the liquid injection module includes a plurality of the liquid injection cups, and the liquid injection cups correspond to the weighing units one by one.

11. The liquid injection system according to claim 6, wherein, The liquid injection module further includes a guiding member disposed on the tray for guiding the movement of the liquid injection cup in its height direction.

12. The liquid injection system according to claim 11, characterized in that, The guiding member is a guiding bracket. A guiding groove is defined between the guiding bracket and the upper surface of the tray. The top wall of the guiding groove is provided with a guiding column extending towards the upper surface of the tray. A guiding hole is provided on the pre-installed support portion, and the guiding column is slidably engaged with the guiding hole to guide the movement of the liquid injection cup in its height direction.

13. A method for injecting liquid into a battery, characterized in that, A liquid injection system applied to the battery according to any one of claims 1-12, wherein the liquid injection module further comprises a liquid injection device and a valve opening device arranged on the liquid injection cup, and the valve opening device has an open state and a closed state; The liquid injection method includes a liquid preparation step, and the liquid preparation step includes: Obtaining the initial weight A1 of the liquid injection cup through a weighing module; Opening the liquid injection valve of the liquid injection device and injecting electrolyte into the liquid injection cup; Obtaining the real-time weight A2 of the liquid injection cup through the weighing module; Confirming whether the liquid preparation requirement is met by comparing the size of A2 - A1 with the target weight A0; If the liquid preparation requirement is met, the liquid preparation is completed.

14. The liquid injection method according to claim 13, wherein The step of confirming whether the liquid preparation requirement is met by comparing the size of A2 - A1 with the target weight A0 includes: If A2 - A1 ≥ A0, it is confirmed that the liquid preparation requirement is met; If A2 - A1 < A0, it is confirmed that the liquid preparation requirement is not met, and electrolyte is continuously injected into the liquid injection cup.

15. The liquid injection method according to claim 14, wherein The step of if A2 - A1 ≥ A0, it is confirmed that the liquid preparation requirement is met, includes: Based on the electrolyte flow rate q of the liquid injection device and the response time t of the liquid injection valve, determining whether to close the liquid injection valve.

16. The liquid injection method according to claim 15, wherein, The step of based on the electrolyte flow rate q of the liquid injection device and the response time t of the liquid injection valve, determining whether to close the liquid injection valve, includes: If A2 - A1 + qt ≥ A0, close the liquid injection valve; If A2 - A1 + qt < A0, open the liquid injection valve and continue to inject electrolyte into the liquid injection cup.

17. The liquid injection method according to claim 14, characterized in that, The step of if A2 - A1 < A0, it is confirmed that the liquid preparation requirement is not met, and electrolyte is continuously injected into the liquid injection cup, further includes: If the liquid preparation requirement is still not met within a predetermined time, the system gives an alarm prompt.

18. The liquid injection method according to claim 13, wherein The battery includes a switch valve having an open state and a closed state, the liquid injection system further comprises a vacuum pumping module independent of the liquid injection module, the liquid injection method further includes a vacuum pumping step, the liquid preparation step is before the vacuum pumping step, or is carried out simultaneously with the vacuum pumping step, and the vacuum pumping step includes: Docking the vacuum pumping pipeline of the vacuum pumping module with the switch valve to make the switch valve in an open state; Controlling the vacuum pumping device of the vacuum pumping module to vacuum the battery; After confirming that the vacuum pumping is completed, separating the vacuum pumping pipeline from the switch valve to make the switch valve in a closed state.

19. The liquid injection method according to claim 18, wherein The liquid injection method further includes a liquid injection step after the vacuum pumping step and the liquid preparation step, and the liquid injection step includes: Docking the valve opening device with the switch valve to make both the valve opening device and the switch valve in an open state; Controlling the liquid injection module to inject liquid into the battery; After confirming that the liquid injection is completed, separating the valve opening device from the switch valve to make both the valve opening device and the switch valve in a closed state.

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