Patent Description:
Formation is a process in which a battery after liquid injection is activated such that a chemical reaction occurs inside the battery to form a solid electrolyte interphase (SEI) film to ensure the operation performance of the battery during subsequent charge/discharge cycles. During this process, the battery will generate a certain amount of gas, and the gas will affect the forming of the SEI film and thus affect the subsequent operation performance of the battery.

At present, in order to prevent the influence of the gas generated during the battery formation process on the forming of the SEI film, it is necessary to maintain a high negative pressure inside the battery during the battery formation process to discharge the generated gas in real time, but this will result in the loss of electrolyte caused by the electrolyte inside the battery being drawn out of a housing.

<CIT> discloses a pressurized liquid injection device for a battery electrode plate, wherein the battery <NUM> comprises a housing with a liquid injection hole and electrode plates in the housing. The pressurized liquid injection device comprises a vacuum chamber <NUM>, a clamp <NUM> for holding the battery <NUM>, a container <NUM> for holding the electrolyte is provided on the clamp <NUM>, and a pipe <NUM> for connecting the liquid injection hole of the battery <NUM> is provided at the lower part of the container <NUM>.

<CIT> discloses a battery vacuum negative pressure formation device, comprising a vacuum generating device <NUM>, a first hose <NUM>, a transition container <NUM>, a second hose <NUM>, a connected structure <NUM>, a connected structure <NUM> and a connected structure <NUM>. One end of the connected structure <NUM>, the connected structure <NUM> and the connected structure <NUM> is sealed and connected with the second hose <NUM>, and the other end is sealed and connected with the liquid injection hole of battery <NUM>. The connected structure <NUM> includes a connected hose <NUM>, a hose connector <NUM>, a plug <NUM>, and a suction cup <NUM> which are sealed and connected in sequence. The suction cup <NUM> is sealed with the liquid injection hole of the battery <NUM>.

<CIT> discloses a battery formation device, comprising a positioning block <NUM>, a drive mechanism <NUM>, a sealing assembly <NUM>, a vacuum mechanism <NUM>, a charge and discharge mechanism <NUM>, and a barrier <NUM>. The vacuum mechanism <NUM> is sealed and communicated with a channel of the sealing assembly <NUM>, and the vacuum mechanism <NUM> can vacuum the inside of the battery through the channel of the sealing assembly <NUM> and the liquid injection hole of the battery.

<CIT> discloses a battery negative pressure formation device, comprising a frame <NUM>, a pallet <NUM>, a lifting mechanism <NUM>, a probe assembly <NUM> and a negative pressure assembly <NUM>. Two probe assemblies <NUM> and one negative pressure assembly <NUM> are combined into a group for working with a battery <NUM>. The negative pressure assembly <NUM> is connected to and communicate with the injection hole <NUM> on the battery cover plate to vacuum the battery <NUM>.

A purpose of the embodiments of the present application is to provide a formation system, which can prevent the loss of electrolyte caused by the electrolyte inside the battery being drawn out of a housing.

In order to solve the technical problem mentioned above, the embodiments of the present application provide a formation system for formation of a battery, the formation system comprising a clamp, a suction nozzle, and a negative pressure source, the clamp being used to clamp the battery, the suction nozzle being disposed corresponding to and opposite to a liquid injection hole of the battery to collect formation exhaust gas from the battery, and the negative pressure source being connected to the suction nozzle to provide negative pressure environment for the suction nozzle, wherein there is a preset distance between the suction nozzle and the liquid injection hole of the battery to prevent electrolyte in the battery from being drawn out.

With regard to the formation system according to the embodiments of the present application, a pressure is applied to the battery by means of the clamp to suppress the expansion of a gap between electrode plates of the battery, suppress the generation of bubbles, and promote the discharge of a formation gas of the battery, so as to ensure that there is no abnormality in the inner interphase of the battery in a normal pressure state to achieve the effect of formation under a normal pressure. In addition, the formation exhaust gas from the battery can be discharged in real time in the negative pressure environment that is created in the suction nozzle by the negative pressure source, and since there is a preset distance between the suction nozzle and the liquid injection hole of the battery, the negative pressure environment does not directly enter the inside of the battery, which can prevent the electrolyte inside the battery from being drawn out so as to prevent the loss of the electrolyte inside the battery.

In some embodiments, the clamp comprises at least two limiting members disposed opposite each other at an interval, the battery is held between the two adjacent limiting members, and the two adjacent limiting members are movable relatively to change a clamping force on the battery. In this way, the clamping force on the battery can be adjusted by the relative movement of the limiting members, and the distance between the limiting members can also be changed by the relative movement of the limiting members, so as to adapt to the clamping of batteries of different sizes, thereby improving the compatibility of the clamp.

In some embodiments, the clamp further comprises a base, on which each of the limiting members is movably disposed. In this way, the base can have a function of bearing the battery, such that the battery can be conveniently placed between the two adjacent limiting members.

In some embodiments, the clamp further comprises a buffer member that is disposed on the side of the limiting member close to the battery and configured to abut against the battery. The buffer member can buffer the clamping force of the clamp on the battery to avoid damages to the battery caused by a sudden change of the clamping force.

In some embodiments, the buffer member has a first surface that abuts against a second surface of the battery, with the orthographic projection of the first surface on the second surface being not exceeding the second surface. The orthographic projection of the first surface of the buffer member on the second surface does not exceed the second surface of the battery, such that the buffer member can avoid an edge part of the battery, and thus the edge part of the battery is not easy to deform by being squeezed and then crushed.

In some embodiments, the first surface of the buffer member is of an arched structure with the middle protruding outwardly.

In some embodiments, the suction nozzle is internally provided with a funnel-shaped channel, with the end of the channel having a larger area being disposed facing the liquid injection hole of the battery, and the other end being connected to the negative pressure source. The suction nozzle is internally provided with the funnel-shaped channel, and the end of the channel having a larger area is disposed facing the liquid injection hole of the battery, such that the area of action of the negative pressure region of the suction nozzle on the liquid injection hole can be increased for better collection of the formation exhaust gas from the battery.

In some embodiments, the formation system further comprises an enclosure, with one end of the enclosure being sleeved on the suction nozzle, and the other end of the enclosure being disposed facing and close to the liquid injection hole of the battery. In this way, the enclosure sleeved on the suction nozzle can have a barrier function on the periphery of the suction nozzle and can prevent the formation exhaust gas from the battery from diffusing into surroundings.

In some embodiments, the formation system further comprises a collection pipeline configured for connecting the negative pressure source and the suction nozzle. In this way, the connection between the negative pressure source and the suction nozzle can be achieved by means of the collection pipeline, the length of the collection pipeline can be set according to the distance between the negative pressure source and the suction nozzle, and during production in a factory, the negative pressure source and the suction nozzle that are far away from each other can be connected by means of the collection pipeline.

In some embodiments, the collection pipeline comprises a delivery pipe, a confluence pipe connected to the delivery pipe, and a plurality of branch pipes connected to the confluence pipe, the negative pressure source being connected to the delivery pipe, and each of the branch pipes being connected to one suction nozzle. In this way, the simultaneous collection of the formation exhaust gas from multiple batteries can be achieved by means of the confluence pipe and the plurality of branch pipes, thereby improving the production efficiency.

In some embodiments, the formation system further comprises a gas-liquid separator, with an inlet end of the gas-liquid separator being connected to the delivery pipe, and an outlet end of the gas-liquid separator being connected to the negative pressure source. By means of providing the gas-liquid separator, the electrolyte in the formation exhaust gas of the battery can be removed by the gas-liquid separator to prevent environmental pollution caused by the electrolyte. In addition, the inlet end of the gas-liquid separator is connected to the delivery pipe, and the outlet end of the gas-liquid separator is connected to the negative pressure source, such that it is not necessary to provide gas-liquid separators in branches of the collection pipeline, and thus the number of gas-liquid separators can be reduced.

The embodiments of the present application provide a formation method for a battery, wherein the formation method includes: clamping the battery; arranging a suction nozzle at a preset distance from a liquid injection hole of the battery; and driving a negative pressure source to enable the suction nozzle to generate a negative pressure.

In some embodiments, the preset distance has a range greater than <NUM> and less than <NUM>.

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of preferred embodiments. The drawings are merely for the purpose of illustrating the preferred embodiments and are not to be construed as limiting the present application. Moreover, like components are denoted by like reference numerals throughout the drawings. In the drawings:.

List of reference signs:
<NUM>. clamp; <NUM>. limiting member; <NUM>. base; <NUM>. buffer member; <NUM>. first surface; <NUM>. intermediate plate; <NUM>. suction nozzle; <NUM>. channel; <NUM>. enclosure; <NUM>. collection pipeline; <NUM>. delivery pipe; <NUM>. confluence pipe; <NUM>. branch pipe; <NUM>. gas-liquid separator; <NUM>. negative pressure source; <NUM>. battery; <NUM>. housing; <NUM>. electrode assembly; <NUM>. end cap; <NUM>. liquid injection hole; <NUM>. second surface.

Embodiments of the technical solutions of the present application will be described in more detail below with reference to the drawings. The following embodiments are merely intended to more clearly illustrate the technical solutions of the present application, so they merely serve as examples, but are not intended to limit the scope of protection of the present application.

Unless otherwise defined, all technical and scientific terms used herein have the same meanings as those commonly understood by those skilled in the art to which the present application belongs. The terms used herein are merely for the purpose of describing specific embodiments, but are not intended to limit the present application. The terms "comprising" and "having" and any variations thereof in the description and the claims of the present application as well as the brief description of the accompanying drawings described above are intended to cover non-exclusive inclusion.

In the description of the embodiments of the present application, the technical terms "first", "second", etc. are merely used for distinguishing different objects, and are not to be construed as indicating or implying relative importance or implicitly indicating the number, particular order or primary-secondary relationship of the technical features modified thereby. In the description of the embodiments of the present application, the phrase "a plurality of" means two or more, unless otherwise explicitly and specifically defined.

The phrase "embodiment" mentioned herein means that the specific features, structures, or characteristics described in conjunction with the embodiment can be encompassed in at least one embodiment of the present application. The phrase at various locations in the description does not necessarily refer to the same embodiment, or an independent or alternative embodiment exclusive of another embodiment. Those skilled in the art understand explicitly or implicitly that the embodiment described herein may be combined with another embodiment.

In the description of the embodiments of the present application, the term "and/or" is merely intended to describe the associated relationship of associated objects, indicating that three relationships can exist, for example, A and/or B can include: the three instances of A alone, A and B simultaneously, and B alone. In addition, the character "/" herein generally indicates an "or" relationship between the associated objects.

In the description of the embodiments of the present application, the term "a plurality of" means two or more (including two), similarly the term "a plurality of groups" means two or more groups (including two groups), and the term "a plurality of pieces" means two or more pieces (including two pieces).

In the description of the embodiments of the present application, the orientation or position relationship indicated by the technical terms "central", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front"; "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or position relationship shown in the drawings and are merely intended to facilitate and simplify the description of the embodiments of the present application, rather than indicating or implying that the device or element considered must have a particular orientation or be constructed and operated in a particular orientation, and therefore not to be construed as limiting the embodiments of the present application.

In the description of the embodiments of the present application, unless otherwise explicitly specified and defined, the technical terms "mounting", "mutual connection", "connection", "fixing", etc. should be understood in a broad sense, for example, they may be a fixed connection, a detachable connection, or an integrated connection; may be a mechanical connection or an electrical connection; and may be a direct connection or an indirect connection through an intermediate medium, and may be communication between interiors of two elements or interaction between the two elements. For those of ordinary skill in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to specific situations.

Formation aims to activate a battery. During the first charge/discharge process of the battery, an electrode material and electrolyte react at a solid-liquid two-phase interphase to form a passivation film layer that covers a surface of the electrode material. This passivation film layer is an interphase layer, and has the characteristics of solid electrolyte. This layer of passivation film is also referred to as a solid electrolyte interphase film, or an SEI film for short. The forming of the SEI film has a crucial influence on the subsequent operation performance of the battery.

At present, in order to facilitate the discharge of gas during the battery formation to prevent the influence of the gas generated during a battery formation process on the forming of the SEI film, during the battery formation process, a negative pressure source is connected to the inside of the battery via a pipeline, and a suction nozzle presses against a liquid injection hole of a battery so as to apply a negative pressure to the inside of the battery to discharge the gas. In this way, the battery is connected to the negative pressure source to enable the inside of the battery to be at a negative pressure, such that the formation exhaust gas from the battery can be drawn out of a housing of the battery in time.

However, the applicants have noted that, when the inside of the battery is at the negative pressure, although the formation exhaust gas from the battery will be drawn out of the housing, the electrolyte inside the battery will also be drawn out of the housing, resulting in the loss of electrolyte.

In order to prevent the loss of electrolyte caused by the electrolyte inside the battery being drawn out of the housing, the applicants have found that a pressure can be applied to the battery by means of a clamp to remove the formation exhaust gas generated inside the battery, and the negative pressure source is separated from the inside of the battery, that is, the negative pressure created by the negative pressure source does not directly enter the inside of the battery, but the negative pressure created by the negative pressure source is only close to the liquid injection hole of the battery. Specifically, the suction nozzle connected to the negative pressure source is spaced apart from the liquid injection hole of the battery by a preset distance.

When this formation system is used, the pressure can be applied to the battery by means of the clamp to promote the discharge of the formation gas from the battery, and the formation exhaust gas from the battery can be collected by means of the suction nozzle connected to the negative pressure source. Since there is a preset distance between the suction nozzle and the liquid injection hole of the battery, it is possible to prevent the electrolyte inside the battery from being drawn out of the housing, and thus prevent the loss of the electrolyte inside the battery.

In addition, since there is no need to allow the inside of the battery to be at a high negative pressure, a negative pressure cup, a pressure regulating valve and a flow valve in a high negative pressure formation system can be omitted, thereby simplifying the negative pressure system and reducing the cost of the negative pressure system.

The formation system according to the embodiment of the present application is used for formation of a battery. As shown in <FIG>, the formation system comprises a clamp <NUM>, a suction nozzle <NUM> and a negative pressure source <NUM>, the clamp <NUM> being used to clamp a battery <NUM>, the suction nozzle <NUM> being disposed corresponding to a liquid injection hole <NUM> of the battery <NUM> to collect formation exhaust gas from the battery <NUM>, and the negative pressure source <NUM> being connected to the suction nozzle <NUM> to provide negative pressure environment for the suction nozzle <NUM>, wherein there is a preset distance between the suction nozzle <NUM> and the liquid injection hole <NUM> of the battery <NUM> to prevent electrolyte in the battery <NUM> from being drawn out.

The battery <NUM> may be a secondary battery or a primary battery, or may be a lithium-sulfur battery, a sodium-ion battery, or a magnesium-ion battery, but is not limited to thereto. The battery <NUM> may be in a form of a cylinder, a flat body, a cuboid, etc..

Referring to <FIG> is a schematic structural exploded view of a battery according to some embodiments of the present application. As shown in <FIG>, the battery <NUM> comprises a housing <NUM>, an electrode assembly <NUM>, an end cap <NUM>, and other functional components.

The housing <NUM> is an assembly that is configured to fit with the end cap <NUM> to form internal environment of the battery <NUM>, wherein the internal environment created may be used for accommodating the electrode assembly <NUM>, electrolyte and other components. The housing <NUM> and the end cap <NUM> may be separate components, and the housing <NUM> may be provided with an opening, at which the end cap <NUM> covers the opening to form the internal environment of the battery <NUM>. Without limitation, the end cap <NUM> may also be integrated with the housing <NUM>. Specifically, the end cap <NUM> and the housing <NUM> can form a common connection surface before other components are placed into the housing, and then the end cap <NUM> covers the housing <NUM> when the interior of the housing <NUM> needs to be packaged. The housing <NUM> may have various shapes and various sizes, for example, in the form of a cuboid, a cylinder, a hexagonal prism, etc. Specifically, the housing <NUM> may be shaped depending on the specific shape and size of the electrode assembly <NUM>. The housing <NUM> may be made of various materials, such as copper, iron, aluminum, stainless steel and an aluminum alloy, which is not specifically limited in the embodiments of the present application.

The electrode assembly <NUM> is a component in the battery <NUM> where an electrochemical reaction occurs. One or more electrode assemblies <NUM> may be contained in the housing <NUM>. The electrode assembly <NUM> is mainly formed by winding or stacking a positive electrode plate and a negative electrode plate, and a separator is usually provided between the positive electrode plate and the negative electrode plate. The portions of the positive electrode plate and the negative electrode plate that have an active material constitute a main body portion of the electrode assembly, and the portions of the positive electrode plate and the negative electrode plate that have no active material each constitute a tab. A positive electrode tab and a negative electrode tab can be both located at one end of the main body portion or respectively at two ends of the main body portion. During the charging and discharging of the battery, a positive active material and a negative active material react with the electrolyte solution, and the tabs are connected to the electrode terminals to form a current loop.

The end cap <NUM> refers to a component that covers an opening of the housing <NUM> to isolate internal environment of the battery <NUM> from external environment. Without limitation, the end cap <NUM> may have a shape adapted to that of the housing <NUM> to fit with the housing <NUM>. Optionally, the end cap <NUM> may be made of a material with certain hardness and strength (such as aluminum alloy), and thus the end cap <NUM> is less prone to deformation when being squeezed or collided, such that the battery <NUM> can have a higher structural strength, and safety performance can also be improved. Functional components, such as electrode terminals, may be provided on the end cap <NUM>. The electrode terminals may be used for electrical connection to the electrode assembly <NUM> for outputting or inputting electrical energy of the battery <NUM>. In some embodiments, a pressure relief mechanism, which is used to release an internal pressure when the internal pressure or temperature of the battery <NUM> reaches a threshold, may be further provided on the end cap <NUM>. The end cap <NUM> may be made of various materials, such as copper, iron, aluminum, stainless steel, an aluminum alloy and plastic, which is not specifically limited in the embodiments of the present application. In some embodiments, an insulating member may be further provided on an inner side of the end cap <NUM>. The insulating member may be used to isolate electrical connection components within the housing <NUM> from the end cap <NUM> so as to reduce the risk of short circuiting. Exemplarily, the insulating member may be made of plastic, rubber, etc..

The liquid injection hole <NUM> is a through hole that is provided in the battery <NUM> and is connected to the inside of the battery <NUM>, and the electrolyte can be injected into the battery <NUM> via the liquid injection hole <NUM>. The liquid injection hole <NUM> may be circular, elliptical or polygonal in shape, and the liquid injection hole <NUM> may be located in the end cap <NUM>, a side surface of the housing <NUM>, or a bottom surface of the housing <NUM>. A plurality of liquid injection holes <NUM> may be provided, so as to improve the liquid injection efficiency of the battery <NUM>. In this case, each liquid injection hole <NUM> is correspondingly provided with a suction nozzle <NUM>.

The clamp <NUM> is a component in the formation system that is used to clamp the battery <NUM> and apply a pressure to the battery <NUM>, and applying a pressure to the battery <NUM> by means of the clamp <NUM> can promote the discharge of the formation gas from the battery <NUM>. The clamp <NUM> can clamp the battery <NUM> by means of a multi-layer plate structure, and the clamp <NUM> can be arranged in a box, in a cabinet, or on a base.

The suction nozzle <NUM> is a component in the formation system that is used to collect the formation exhaust gas from the battery <NUM>, and the suction nozzle <NUM> is disposed facing the liquid injection hole <NUM> of the battery <NUM>, and can draw the formation exhaust gas from the battery <NUM> in the negative pressure environment. The suction nozzle <NUM> may be either directly or indirectly connected to the negative pressure source <NUM>. The suction nozzle <NUM> may be configured in the form of a cylinder, a prism or a circular truncated cone. The suction nozzle <NUM> may be made of a corrosion-resistant material, such as ethylene-propylene-diene monomer.

The negative pressure source <NUM> is a component in the formation system that is used to create negative pressure environment for the suction nozzle <NUM>, and the negative pressure source <NUM> may be a common vacuum pumping device, such as a vacuum pump.

With regard to the formation system according to the embodiments of the present application, a pressure is applied to the battery <NUM> by means of the clamp <NUM>, which can suppress the expansion of a gap between electrode plates of the battery <NUM> and suppress the generation of bubbles, and can also promote the discharge of the formation gas from the battery <NUM>. In this way, it is possible to ensure that there is no abnormality in the inner interphase of the battery <NUM> in a normal pressure state, so as to achieve the effect of formation under a normal pressure. In addition, the formation exhaust gas in the battery <NUM> discharged from the liquid injection hole is removed in the negative pressure environment that is created in the suction nozzle <NUM> by the negative pressure source <NUM>. Since there is a preset distance between the suction nozzle <NUM> and the liquid injection hole <NUM> of the battery <NUM>, the negative pressure environment does not directly enter the inside of the battery <NUM>, which can prevent the electrolyte inside the battery <NUM> from being drawn out so as to prevent the loss of the electrolyte inside the battery <NUM>.

In some embodiments, the preset distance d between the suction nozzle <NUM> and the liquid injection hole <NUM> of the battery <NUM> may be between <NUM> and <NUM> millimeters, so as to prevent environmental pollution caused by the formation exhaust gas of the battery <NUM> being not drawn into the suction nozzle <NUM> and then escaping into the external environment due to the too large distance between the suction nozzle <NUM> and the liquid injection hole <NUM> of the battery <NUM>. In addition, it is possible to prevent the electrolyte inside the battery <NUM> from being drawn out caused by the suction nozzle <NUM> pressing in the liquid injection hole <NUM> of the battery <NUM>.

The clamp <NUM> comprises at least two limiting members <NUM> disposed opposite each other at an interval, the battery <NUM> is held between the two adjacent limiting members <NUM>, and the two adjacent limiting members <NUM> can move relatively to change the clamping force on the battery <NUM>.

The limiting member <NUM> may be plate-like, the limiting member <NUM> is a component in the clamp <NUM> that is configured to be clamped on the battery <NUM>, and the number of the limiting members <NUM> can be determined according to the number of the batteries <NUM> to be clamped. In addition, the two adjacent limiting members <NUM> can move relatively, that is, in the two adjacent limiting members <NUM>, one limiting member <NUM> can move close to/away from the other limiting member <NUM>, or the two limiting members <NUM> move simultaneously to change the distance between the two limiting members <NUM>.

The magnitude of the clamping force on the battery <NUM> can be adjusted by means of the relative movement of the limiting members <NUM>. Moreover, the distance between the limiting members <NUM> can be changed by the relative movement of the limiting members <NUM> so as to adapt to the clamping of the batteries <NUM> of different sizes, thereby improving the compatibility of the clamp <NUM>.

In some embodiments of the present application, optionally, the clamp <NUM> further comprises a base <NUM>, and each limiting member <NUM> is movably disposed on the base <NUM>.

The base <NUM> is a component in the clamp <NUM> that has a supporting function, and the base <NUM> may be provided as a plate. In the formation system as shown in <FIG>, the clamp <NUM> can simultaneously clamp multiple batteries <NUM>, and optionally, the limiting members <NUM> may be of a plate-like structure, a plurality of limiting members <NUM> are sequentially disposed on one base <NUM> in a preset direction, one battery <NUM> can be held between two adjacent limiting members <NUM>, and each limiting member <NUM> is movably disposed on the base <NUM>. The base <NUM> is further provided with two stop members located on the outermost side of the plurality of limiting members <NUM>, and the two stop members can limit the movement of the plurality of limiting members within a certain range. One of the stop members may be provided with a driving structure that can force the plurality of limiting members <NUM> to move on the base <NUM> to apply a pressure to the batteries <NUM>. The driving structure may be a driving electric motor, or a manual pressure rod to apply a pressure. The movement of each limiting member <NUM> on the base <NUM> can be achieved by providing a guide rod between the two stop members, a plurality of guide rods may be provided between the two stop members, and the plurality of limiting members <NUM> may slide along the plurality of guide rods, so as to achieve the movement of the plurality of limiting members <NUM> on the base <NUM>.

The base <NUM> can have a function of bearing the battery <NUM>. When the battery <NUM> is placed between the two adjacent limiting members <NUM>, the bottom of the battery <NUM> can be supported on the base <NUM>, so as to conveniently place the battery <NUM> between the two adjacent limiting members <NUM> and locate a clamping position of the battery <NUM>.

The clamp <NUM> further comprises a buffer member <NUM>. The buffer member <NUM> is disposed on the side of the limiting member <NUM> close to the battery <NUM> and configured to abut against the battery <NUM>.

The buffer member <NUM> is a component in the clamp <NUM> that is configured to abut against the battery <NUM>, and the buffer member <NUM> can buffer the clamping force of the clamp <NUM> on the battery <NUM>, such that the damage to the battery <NUM> caused by a sudden change in the clamping force can be avoided by means of the buffer member <NUM>. Optionally, the buffer member <NUM> may be a pad, such as a silicone pad or a rubber pad, having a buffering function, which is not limited in the embodiments of the present application.

In some embodiments of the present application, optionally, the buffer member <NUM> has a first surface <NUM>, the first surface <NUM> abutting against a second surface <NUM> of the battery <NUM>, and the orthographic projection of the first surface <NUM> on the second surface <NUM> not exceeding the second surface <NUM>.

The buffer member <NUM> has two opposite surfaces. One of the two surfaces of the buffer member <NUM> is attached to the limiting member <NUM>, that is, the buffer member <NUM> is fixed to the limiting member <NUM>, and the other surface of the buffer member <NUM>, that is, the first surface <NUM>, abuts against the battery <NUM>. In the battery clamping structure as shown in <FIG>, the battery <NUM> is clamped between the two limiting members <NUM>, the buffer member <NUM> on each limiting member <NUM> transfers the pressure to the battery <NUM>, the edge of the buffer member <NUM> is located within the edge of the housing of the battery <NUM>, and the buffer member <NUM> deforms during the pressure transfer process. The amounts of deformation of the parts of the buffer member <NUM> are different depending on the degree of hardness of the housing of the battery <NUM>, and after avoiding the relatively hard part of the housing of the battery <NUM>, the buffer member <NUM> can better transfer the pressure into the battery <NUM> to tightly press the electrode assembly <NUM> in the housing of the battery <NUM>. In addition, the edge part of the battery <NUM> is not easy to deform by being squeezed and then crushed.

The first surface <NUM> of the buffer member <NUM> is of an arched structure with the middle protruding outwardly. In the formation process, during the process of the clamp <NUM> clamping the battery <NUM>, the middle of the second surface <NUM> of the battery <NUM> has relatively large degree of deformation, such that the configuration of the first surface <NUM> of the buffer member <NUM> as an arched structure with the middle protruding outward can increase the clamping force on the battery <NUM>, reduce the gap between the electrode assemblies <NUM>, and reduce the generation of gas during the formation process of the battery <NUM>, thereby improving the formation quality.

In this way, the first surface <NUM> of the buffer member <NUM> can avoid the edge of the housing of the battery <NUM> to avoid the relatively hard part of the battery <NUM>, so as to better adapt to the pressure applied to the battery <NUM> to improve the squeezing effect on the battery <NUM> to tightly press the electrode assembly <NUM> inside the battery <NUM>.

In some embodiments of the present application, optionally, the suction nozzle <NUM> is internally provided with a funnel-shaped channel <NUM>, with the end of the channel <NUM> having a larger area being disposed facing the liquid injection hole <NUM> of the battery <NUM>, and the other end being connected to the negative pressure source <NUM>.

The formation exhaust gas from the battery <NUM> can be better collected by means of the funnel-shaped channel <NUM> inside the suction nozzle <NUM>. The funnel-shaped channel <NUM> can increase the opening area of one of the ends of the suction nozzle <NUM>, and the formation exhaust gas from the battery <NUM> can be collected in a wider range by means of increasing the opening area of the suction nozzle <NUM> facing the liquid injection hole <NUM> of the battery <NUM>.

In some embodiments of the present application, optionally, the formation system further comprises an enclosure <NUM>, with one end of the enclosure <NUM> being sleeved on the suction nozzle <NUM>, and the other end of the enclosure <NUM> being disposed facing and close to the liquid injection hole <NUM> of the battery <NUM>.

The enclosure <NUM> is disposed on the suction nozzle <NUM> for preventing the formation exhaust gas of the battery <NUM> from diffusing to the surroundings. Optionally, the enclosure <NUM> may be of a hollow structure, and the enclosure <NUM> may be funnel-shaped, with the end of the enclosure <NUM> having a larger opening area facing the liquid injection hole <NUM> of the battery <NUM>. The enclosure <NUM> may be closer to the liquid injection hole <NUM> of the battery <NUM> than the suction nozzle <NUM>, so as to prevent diffusion of the formation exhaust gas from the battery <NUM>.

The enclosure <NUM> may have a barrier function around the liquid injection hole <NUM> of the battery <NUM> to prevent the formation exhaust gas from the battery <NUM> from diffusing to the surroundings so as to avoid the pollution to the surroundings caused by the formation exhaust gas from the battery <NUM>.

In some embodiments of the present application, optionally, the formation system further comprises a collection pipeline <NUM>. The collection pipeline <NUM> is configured for connecting the negative pressure source <NUM> and the suction nozzle <NUM>.

The collection pipeline <NUM> can facilitate the connection between the negative pressure source <NUM> and the suction nozzle <NUM>. The length of the collection pipeline <NUM> can be set according to the distance between the negative pressure source <NUM> and the suction nozzle <NUM>, and during production in a factory, the negative pressure source <NUM> and the suction nozzle <NUM> that are far away from each other can be connected by means of the collection pipeline <NUM>.

In some embodiments of the present application, optionally, the collection pipeline <NUM> comprises a delivery pipe <NUM>, a confluence pipe <NUM> connected to the delivery pipe <NUM>, and a plurality of branch pipes <NUM> connected to the confluence pipe <NUM>, the negative pressure source <NUM> being connected to the delivery pipe <NUM>, and each branch pipe <NUM> being connected to one suction nozzle <NUM>.

In this way, the simultaneous collection of the formation exhaust gas from multiple batteries <NUM> can be achieved by means of the confluence pipe <NUM> and the plurality of branch pipes <NUM>, thereby improving the production efficiency.

Accordingly, a plurality of clamps <NUM> may be provided. The plurality of clamps <NUM> are disposed side by side, and each clamp <NUM> can simultaneously apply a pressure to multiple batteries <NUM>. The liquid injection hole <NUM> of each battery <NUM> corresponds to one suction nozzle <NUM>, and the formation exhaust gas collected by each suction nozzle <NUM> converges via the confluence pipe <NUM> and then reaches the delivery pipe <NUM>, and is then transferred and discharged via the delivery pipe <NUM>. In addition, each clamp <NUM> can simultaneously apply a pressure to two rows of batteries <NUM>, that is, an intermediate plate <NUM> is provided on the base <NUM> of the clamp <NUM>, and a group of batteries <NUM> can be placed on either side of the intermediate plate <NUM>. Accordingly, each confluence pipe <NUM> corresponding to each clamp <NUM> can simultaneously collect the formation exhaust gas from two groups of batteries <NUM>, that is, the plurality of branch pipes <NUM> connected to each confluence pipe <NUM> can be disposed oppositely on two sides of the confluence pipe <NUM>, such that the number of the batteries <NUM> clamped by each clamp <NUM> can be increased, thereby improving the formation efficiency of the formation system.

In a specific formation system as shown in <FIG>, two clamps <NUM> are disposed side by side, each clamp <NUM> corresponds to one confluence pipe <NUM>, each confluence pipe <NUM> is connected to twenty-four branch pipes <NUM>, the twenty-four branch pipes <NUM> are divided into two groups, and the two groups of branch pipes <NUM> are disposed oppositely on two sides of the confluence pipe <NUM>. Each clamp <NUM> can simultaneously apply a pressure to twenty-four batteries <NUM>, and the formation exhaust gas from each battery <NUM> can be collected via the corresponding suction nozzle <NUM>, sequentially pass through the branch pipe <NUM> and the confluence pipe <NUM> and then reach the delivery pipe <NUM>, and then be transferred and discharged via the delivery pipe <NUM>.

The plurality of clamps <NUM> are provided, such that the number of batteries <NUM> simultaneously subjected to formation by the formation system can be increased, thereby improving the production efficiency.

In some embodiments of the present application, optionally, the formation system further comprises a gas-liquid separator <NUM>, with an inlet end of the gas-liquid separator <NUM> being connected to the delivery pipe <NUM>, and an outlet end of the gas-liquid separator <NUM> being connected to the negative pressure source <NUM>.

The gas-liquid separator <NUM> can filter the formation exhaust gas from the battery <NUM> to remove the electrolyte in the formation exhaust gas, so as to prevent environmental pollution caused by the electrolyte. In addition, the inlet end of the gas-liquid separator <NUM> is connected to the delivery pipe <NUM>, and the outlet end of the gas-liquid separator <NUM> is connected to the negative pressure source <NUM>, such that it is not necessary to provide gas-liquid separators <NUM> in the branches of the collection pipeline <NUM>, and thus the number of gas-liquid separators <NUM> in the formation system can be reduced.

Claim 1:
A formation system for formation of a battery (<NUM>), wherein the formation system comprises:
the battery (<NUM>);
a clamp (<NUM>) for clamping the battery (<NUM>);
a suction nozzle (<NUM>) disposed corresponding to and opposite to a liquid injection hole (<NUM>) of the battery (<NUM>) to collect a formation exhaust gas of the battery (<NUM>); and
a negative pressure source (<NUM>) connected to the suction nozzle (<NUM>) to provide negative pressure environment for the suction nozzle (<NUM>);
wherein there is a preset distance between the suction nozzle (<NUM>) and the liquid injection hole (<NUM>) to prevent electrolyte in the battery (<NUM>) from being drawn out;
the clamp (<NUM>) comprises at least two limiting members (<NUM>) disposed opposite each other at an interval, the battery (<NUM>) is held between the two adjacent limiting members (<NUM>), and the two adjacent limiting member (<NUM>) are movable relatively to change a clamping force on the battery (<NUM>);
the clamp (<NUM>) further comprises a buffer member (<NUM>) that is disposed on the side of the limiting member (<NUM>) close to the battery (<NUM>) and configured to abut against the battery (<NUM>); and
a first surface (<NUM>) of the buffer member (<NUM>) is of an arched structure with the middle protruding outwardly, and the first surface (<NUM>) abuts against the battery (<NUM>).