Solid-state lithium ion battery with stable and safe structure and preparation process of solid-state lithium ion battery

Abstract

The invention relates to the technical field of new energy automobile batteries, in particular to a solid-state lithium ion battery with a stable and safe structure and a preparation technology thereof.The solid-state lithium ion battery comprises a hard shell, a battery negative electrode, a battery positive electrode and a solid-state electrolyte, and the battery negative electrode, the battery positive electrode and the solid-state electrolyte are arranged in the hard shell; a pressure-equalizing side plate is fixedly arranged on the arc telescopic sleeve, and the pressure-equalizing side plate, the arc telescopic sleeve and the hard shell are matched to form a closed cavity; according to the solid-state lithium ion battery disclosed by the invention, through the cooperation of the voltage-sharing side plates, the arc-bending telescopic sleeve, the voltage regulating structure and the like, the contact pressure among the battery cathode, the battery anode and the solid-state electrolyte can be automatically increased during large-current charging and discharging of a new energy automobile, and the battery performance is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of new energy vehicle batteries, and specifically to a solid-state lithium-ion battery with stable and safe structure and its preparation process. Background Art

[0002] A solid-state lithium-ion battery is a new type of lithium secondary battery for new energy vehicles. Its electrolyte is solid rather than liquid. During charging, lithium ions are released from the positive electrode material, migrate through the solid electrolyte to the negative electrode, and are embedded in the negative electrode material; during discharging, on the contrary, lithium ions are released from the negative electrode and return to the positive electrode through the solid electrolyte. Compared with traditional liquid electrolyte batteries, it has higher safety and service life, so it has good application prospects in the field of new energy electric vehicles.

[0003] In actual use scenarios, new energy vehicles have emergency acceleration scenarios such as 0-100 km / h acceleration tests. At this time, there are high requirements for the instantaneous large-current discharge capacity of the battery. It is extremely important to improve the instantaneous large-current charge and discharge performance of solid-state lithium-ion batteries. In the prior art, to improve the instantaneous large-current charge and discharge performance of solid-state lithium-ion batteries for new energy vehicles, it can only be achieved by calculating parameters such as battery materials, ratios, and surface densities. This method is limited by material and technical bottlenecks and will ultimately have certain limitations and cannot dynamically change the charge and discharge performance of solid-state lithium-ion batteries for new energy vehicles. Summary of the Invention

[0004] The purpose of the present invention is to provide a solid-state lithium-ion battery with stable and safe structure and its preparation process to solve the problems raised in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A solid-state lithium-ion battery with stable and safe structure includes a hard shell and a battery negative electrode, a battery positive electrode, and a solid electrolyte arranged inside the hard shell. An arc-shaped telescopic sleeve is arranged on the inner wall surface of the hard shell, and a pressure equalizing side plate is fixedly arranged on the arc-shaped telescopic sleeve. The pressure equalizing side plate, the arc-shaped telescopic sleeve, and the hard shell cooperate to form a closed cavity; when the air pressure in the above closed cavity changes, the contact pressure between the battery negative electrode, the battery positive electrode, and the solid electrolyte can be changed through the pressure equalizing side plate; a bottom clamping cavity is opened at the bottom of the hard shell, and a pressure regulating structure is arranged in the bottom clamping cavity. The pressure regulating structure can regulate the air pressure in the closed cavity formed by the pressure equalizing side plate, the arc-shaped telescopic sleeve, and the hard shell.

[0006] The pressure regulating structure includes an annular eaves, a stator coil, and a permanent magnet rotor ring. The annular eaves is fixedly arranged at the inner upper surface position of the bottom clamping cavity. The stator coil is fixedly arranged in the annular eaves, and the permanent magnet rotor ring is arranged in the permanent magnet rotor ring. After the stator coil is energized with an automatically commutating current, it can drive the permanent magnet rotor ring to rotate.

[0007] A rotor inner disc is fixedly arranged at the central position of the permanent magnet rotor ring. An upper shaft of the inner disc is fixedly arranged on the upper surface of the rotor inner disc. A rotating limit sleeve is fixedly arranged at the position of the inner upper surface of the bottom clamping cavity. The upper shaft of the inner disc is rotationally limited and inserted into the rotating limit sleeve.

[0008] A driving small gear is fixedly arranged on the lower surface of the rotor inner disc. A large gear ring is meshed outside the driving small gear. A central worm is fixedly arranged at the central position of the large gear ring. A matching worm gear is meshed outside the central worm.

[0009] A limiting short shaft is fixedly arranged on one side of the matching worm gear. A short shaft limiting plate is sleeved outside the limiting short shaft. The short shaft limiting plate is fixedly installed on the inner wall surface of the bottom clamping cavity. A lead screw is coaxially fixedly arranged on the other side of the matching worm gear. A telescopic square tube is arranged outside the lead screw. A lead screw matching part is fixedly arranged inside the telescopic square tube. The lead screw is in spiral fit with the lead screw matching part.

[0010] The telescopic square tube is sleeved with a square tube outer sleeve. The square tube outer sleeve is fixedly installed on the inner wall surface of the bottom clamping cavity. When the lead screw rotates, the telescopic square tube can be driven to move along the axis direction of the lead screw.

[0011] A voltage transformation cavity is fixedly arranged on the inner wall surface of the bottom clamping cavity. A voltage transformation piston is arranged in the voltage transformation cavity. The voltage transformation piston is in airtight contact with the voltage transformation cavity. The voltage transformation piston is fixedly installed with the telescopic square tube. The movement of the telescopic square tube drives the movement of the voltage transformation piston. A convex rib is fixedly arranged on the inner wall surface of the bottom clamping cavity.

[0012] A rib inner cavity is opened in the convex rib. The rib inner cavity is communicated with the closed cavity formed by the pressure equalizing side plate, the arc-shaped telescopic sleeve and the hard shell. A communication pipeline is fixedly arranged on the inner wall surface of the bottom clamping cavity. The voltage transformation cavity is communicated with the rib inner cavity through the communication pipeline. A pressure sensor for detecting the internal air pressure of the rib inner cavity is installed on the convex rib.

[0013] A detection attached rib is fixedly arranged on the convex rib. A cylindrical cavity is opened in the detection attached rib. The axis of the cylindrical cavity is parallel to the axis of the arc-shaped telescopic sleeve. A cylindrical iron core is arranged in the cylindrical cavity. A return spring and a detection contact rod are respectively arranged on both sides of the cylindrical iron core. The cylindrical iron core is in the middle position of the cylindrical cavity under the elastic support of the return spring. Breathing groove slits are respectively opened through the two ends of the cylindrical cavity. An electromagnetic switch air valve is installed on the convex rib. When the electromagnetic switch air valve is opened, the rib inner cavity is communicated with the outside atmosphere through the electromagnetic switch air valve. When the cylindrical iron core contacts the detection contact rod, the electromagnetic switch air valve is controlled to be opened.

[0014] A preparation process of a solid-state lithium-ion battery with stable and safe structure, the process comprising the following steps: Step 1, weigh the positive electrode active material, conductive agent and binder, dissolve the conductive agent and binder in an organic solvent to form a glue solution; add the positive electrode active material to the glue solution, mix evenly to make a positive electrode slurry, coat the positive electrode slurry on an aluminum foil current collector, dry and roll, and cut into appropriate sizes to obtain a battery positive electrode; Step 2, select a solid electrolyte material and pre-treat it, and prepare a solid electrolyte by pulsed laser deposition method; Step 3, weigh the negative electrode active material, conductive agent and binder, dissolve the binder in water to form a glue solution, add the conductive agent and active material and stir to form a negative electrode slurry, coat the negative electrode slurry on a copper foil current collector, dry, roll and cut to obtain a battery negative electrode; Step 4, stack the battery positive electrode, solid electrolyte and battery negative electrode in sequence, coat an interface modifier between the stacked surfaces, hot-press to make each layer fit, and then encapsulate it in a rigid outer shell to complete the preparation; Step 5, connect the battery test equipment, and perform the first charge and discharge formation with a low current density to activate the electrochemically active substances.

[0015] Compared with the prior art, the beneficial effects of the present invention are: The solid-state lithium-ion battery of the present invention, through the cooperation of the voltage equalizing side plates, arc-bending expansion sleeves and voltage regulating structures provided, can automatically increase the contact pressure between the battery negative electrode, battery positive electrode and solid electrolyte during high-current charging and discharging of new energy vehicles, improving the battery performance; there may be microscopic pores or unevenness in the contact between the electrode and the solid electrolyte. When pressure is applied, it can make the electrode material and the solid electrolyte fit more closely at the microscopic scale, reduce the interface resistance, and reduce the resistance generated due to poor contact, thereby improving the charge and discharge performance of the battery. During low-current charging and discharging or static state, it can automatically reduce the contact pressure between the battery negative electrode, battery positive electrode and solid electrolyte, reduce the mechanical stress on the electrode and solid electrolyte, and extend their service life.

[0016] The voltage regulating structure of the present invention can provide a greater adjustment pressure in an extremely flat and limited space through its structural setting, and is more adaptable to the battery structure.

[0017] Through the cooperation of structures such as the cylindrical cavity, cylindrical iron core and arc-bending expansion sleeve provided by the present invention, when it detects a collision impact parallel to the axis direction of the arc-bending expansion sleeve of a new energy vehicle, it can automatically open the electromagnetic switch air valve, so that the inside of the arc-bending expansion sleeve is depressurized, making the support of the arc-bending expansion sleeve softer, providing better aftershock buffering for structures such as the solid electrolyte, and reducing the probability of the solid electrolyte cracking. Description of the Drawings

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0019] Figure 2 This is a schematic diagram of a three-dimensional half-section at the ribbed strip of the present invention.

[0020] Figure 3 is Figure 2 an enlarged schematic diagram of area A in

[0021] Figure 4 This is a schematic diagram of a three-dimensional half-section at the central worm of the present invention.

[0022] Figure 5 is Figure 4 an enlarged schematic diagram of area B in

[0023] Figure 6 This is a schematic diagram of a three-dimensional half-section at the telescopic square tube of the present invention.

[0024] Figure 7 is Figure 6 an enlarged schematic diagram of area C in

[0025] Figure 8 This is a schematic diagram of the internal structure of the bottom clamping cavity of the present invention.

[0026] In the figure: 1, hard outer shell; 2, battery negative electrode; 3, battery positive electrode; 4, solid electrolyte; 5, equalizing side plate; 6, arc-shaped telescopic sleeve; 7, bottom clamping cavity; 701, annular eaves; 702, stator coil; 703, permanent magnet rotor ring; 704, inner rotor disk; 705, upper shaft of the inner disk; 706, rotation limiting sleeve; 707, driving small gear; 708, large gear ring; 709, central worm; 710, mating worm gear; 711, limiting short shaft; 712, short shaft limiting plate; 713, lead screw; 714, telescopic square tube; 715, lead screw mating part; 716, outer sleeve of the square tube; 717, voltage transformation cavity; 718, voltage transformation piston; 719, ribbed strip; 720, inner cavity of the rib; 721, connecting pipeline; 722, air pressure sensor; 723, detection attached rib; 724, cylindrical cavity; 725, cylindrical iron core; 726, return spring; 727, detection contact rod; 728, breathing groove; 729, electromagnetic switch air valve. Detailed implementation manners

[0027] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0028] Please refer to Figures 1 to 8 , the present invention provides a technical solution: a solid-state lithium-ion battery with stable and safe structure, as shown in Figure 2 . It includes a rigid outer shell 1 and a battery negative electrode 2, a battery positive electrode 3, and a solid electrolyte 4 arranged inside the rigid outer shell 1. An arc-shaped telescopic sleeve 6 is arranged on the inner wall surface of the rigid outer shell 1, and a pressure equalizing side plate 5 is fixedly arranged on the arc-shaped telescopic sleeve 6. The pressure equalizing side plate 5, the arc-shaped telescopic sleeve 6 and the rigid outer shell 1 cooperate to form a closed cavity; when the air pressure in the above-mentioned closed cavity changes, the contact pressure between the battery negative electrode 2, the battery positive electrode 3 and the solid electrolyte 4 can be changed through the pressure equalizing side plate 5; a bottom clamping cavity 7 is opened at the bottom of the rigid outer shell 1, and a pressure regulating structure is arranged in the bottom clamping cavity 7, and the pressure regulating structure can regulate the air pressure in the closed cavity formed by the pressure equalizing side plate 5, the arc-shaped telescopic sleeve 6 and the rigid outer shell 1.

[0029] The pressure regulating structure includes an annular eaves 701, a stator coil 702 and a permanent magnet rotor ring 703. The permanent magnet rotor ring 703 is formed by arranging permanent magnets in a circumferential array. The annular eaves 701 is fixedly arranged at the inner upper surface position of the bottom clamping cavity 7, and the stator coil 702 is fixedly arranged in the annular eaves 701. There is a permanent magnet rotor ring 703 in the permanent magnet rotor ring 703. After the stator coil 702 is energized with an automatically commutating current, it can drive the permanent magnet rotor ring 703 to rotate. A rotor inner disc 704 is fixedly arranged at the central position of the permanent magnet rotor ring 703, an inner disc upper shaft 705 is fixedly arranged on the upper surface of the rotor inner disc 704, and a rotation limiting sleeve 706 is fixedly arranged at the inner upper surface position of the bottom clamping cavity 7. The inner disc upper shaft 705 is rotationally limited and inserted into the rotation limiting sleeve 706. A driving small gear 707 is fixedly arranged on the lower surface of the rotor inner disc 704, a large gear ring 708 is externally meshed with the driving small gear 707, a central worm 709 is fixedly arranged at the central position of the large gear ring 708, and a matching worm gear 710 is externally meshed with the central worm 709.

[0030] A limiting short shaft 711 is fixedly arranged on one side of the matching worm gear 710, a short shaft limiting plate 712 is sleeved on the outside of the limiting short shaft 711, and the short shaft limiting plate 712 is fixedly installed on the inner wall surface of the bottom clamping cavity 7. A lead screw 713 is coaxially fixedly arranged on the other side of the matching worm gear 710. A telescopic square tube 714 is arranged on the outside of the lead screw 713, a lead screw matching part 715 is fixedly arranged inside the telescopic square tube 714, and the lead screw 713 is in spiral cooperation with the lead screw matching part 715. The outside of the telescopic square tube 714 is sleeved with a square tube outer sleeve 716, and the square tube outer sleeve 716 is fixedly installed on the inner wall surface of the bottom clamping cavity 7. When the lead screw 713 rotates, it can drive the telescopic square tube 714 to move along the axis direction of the lead screw 713.

[0031] On the inner wall surface of the bottom clamping cavity 7, a variable-pressure cavity 717 is fixedly arranged. A variable-pressure piston 718 is arranged in the variable-pressure cavity 717. The variable-pressure piston 718 is in airtight contact with the variable-pressure cavity 717. The variable-pressure piston 718 is fixedly installed with the telescopic square tube 714. The movement of the telescopic square tube 714 drives the movement of the variable-pressure piston 718. On the inner wall surface of the bottom clamping cavity 7, a convex rib 719 is fixedly arranged. A rib inner cavity 720 is formed in the convex rib 719. The rib inner cavity 720 is communicated with the closed cavity formed by the pressure equalizing side plate 5, the arc-shaped telescopic sleeve 6 and the hard shell 1. On the inner wall surface of the bottom clamping cavity 7, a communication pipeline 721 is fixedly arranged. The variable-pressure cavity 717 is communicated with the rib inner cavity 720 through the communication pipeline 721. A pressure sensor 722 for detecting the air pressure inside the rib inner cavity 720 is installed on the convex rib 719.

[0032] A detection attached rib 723 is fixedly arranged on the convex rib 719. A cylindrical cavity 724 is formed in the detection attached rib 723. The axis of the cylindrical cavity 724 is parallel to the axis of the arc-shaped telescopic sleeve 6. A cylindrical iron core 725 is arranged in the cylindrical cavity 724. A return spring 726 and a detection contact rod 727 are respectively arranged on both sides of the cylindrical iron core 725. The cylindrical iron core 725 is in the middle position of the cylindrical cavity 724 under the elastic support of the return spring 726. Breathing slot seams 728 are respectively formed through the two ends of the cylindrical cavity 724. An electromagnetic switch air valve 729 is installed on the convex rib 719. When the electromagnetic switch air valve 729 is opened, the rib inner cavity 720 is communicated with the outside atmosphere through the electromagnetic switch air valve 729; when the cylindrical iron core 725 contacts the detection contact rod 727, the electromagnetic switch air valve 729 is controlled to open. The contact detection between the cylindrical iron core 725 and the detection contact rod 727 is realized by detecting the conductivity between the two through current.

[0033] A preparation process of a solid-state lithium-ion battery with stable and safe structure, the process comprising the following steps: Step 1, weigh the positive electrode active material, conductive agent and binder. The positive electrode active material is lithium iron phosphate, the conductive agent is acetylene black, and the binder is polyvinylidene fluoride. Dissolve the conductive agent and binder in an organic solvent to form a glue solution; add the positive electrode active material to the glue solution, mix evenly to make a positive electrode slurry, coat the positive electrode slurry on an aluminum foil current collector, dry and roll it, and cut it into a suitable size to obtain the battery positive electrode 3; Step 2, select a solid electrolyte material and pre-treat it. The solid electrolyte material includes garnet-type solid electrolyte and sulfide solid electrolyte. Use pulsed laser deposition method to prepare the solid electrolyte 4; in a high-vacuum environment, use a pulsed laser beam to irradiate the solid electrolyte target, so that the atoms or molecules on the surface of the target evaporate and deposit on the substrate to form the solid electrolyte.

[0034] Step 3: Weigh the negative electrode active material, conductive agent, and binder. The negative electrode active material can be graphite. Dissolve the binder in water to make a colloidal solution, add the conductive agent and the active material, and stir to form a negative electrode slurry. Coat the negative electrode slurry on the copper foil current collector, dry, roll, and cut to obtain the battery negative electrode 2. Step 4: Stack the battery positive electrode 3, solid electrolyte 4, and battery negative electrode 2 in sequence in a glove box. Coat an interface modifier between the stacked surfaces, and perform hot pressing to make each layer adhere. Then, encapsulate it into the hard shell 1 to complete the preparation. Step 5: Connect the battery test equipment and perform the first charge and discharge formation with a low current density to activate the electrochemically active substances.

[0035] The solid-state lithium-ion battery of the present invention is mainly applied to new energy vehicles, and is mainly targeted at new energy vehicles with high requirements for instantaneous charge and discharge performance but low requirements for energy density, such as competitive new energy vehicles for short-distance driving. Short-distance track competitions do not require long-distance driving, but have extremely high requirements for instantaneous discharge performance.

[0036] When it is in use, an automatically commutated current is passed through the stator coil 702 through an electronic commutator to drive the permanent magnet rotor ring 703 to rotate. The above-mentioned electronic commutator is an existing device, which detects the position of the permanent magnet rotor ring 703 through a position sensor, and then controls the on / off and direction of the current according to the position signal, which will not be elaborated here. When the permanent magnet rotor ring 703 rotates, the driving small gear 707 drives the large gear ring 708 to rotate. Since the diameter of the large gear ring 708 is larger than that of the driving small gear 707, torque amplification is achieved here. The large gear ring 708 drives the central worm 709 to rotate, and the central worm 709 drives the mating worm gear 710 to rotate, and secondary torque amplification and self-locking are achieved through the worm and worm gear structure. As Figure 7 shown in, when the mating worm gear 710 rotates, it drives the lead screw 713 to rotate, so that the telescopic square tube 714 and the variable pressure piston 718 axially expand and contract for adjustment.

[0037] When a solid-state lithium-ion battery needs to be charged and discharged with a large current, the variable-pressure piston 718 is controlled to squeeze towards the inside of the variable-pressure cavity 717. The airflow in the variable-pressure cavity 717 enters the rib inner cavity 720 through the connecting pipeline 721, and finally enters the closed cavity formed by the pressure-equalizing side plate 5, the arc-bending expansion sleeve 6 and the hard shell 1. The arc-bending expansion sleeve 6 expands and elongates, so that the extrusion pressure of the pressure-equalizing side plate 5 on the battery negative electrode 2, the battery positive electrode 3 and the solid electrolyte 4 is increased. After the pressure is applied, the battery negative electrode 2, the battery positive electrode 3 and the solid electrolyte 4 can be more closely attached on the micro scale. This close contact can reduce the interface resistance. In a solid-state battery, the interface resistance is one of the important factors affecting the battery performance. A high interface resistance will cause the migration of ions at the interface to be hindered during the charge and discharge process, resulting in additional energy loss. By applying pressure, more ion conduction channels can be formed at the interface, reducing the resistance caused by poor contact, thereby improving the charge and discharge efficiency of the battery. The air pressure in the rib inner cavity 720 and the closed cavity is detected by the air pressure sensor 722 to form a closed-loop control to avoid damaging the structure such as the solid electrolyte 4 due to excessive pressure.

[0038] As Figure 3 shown in the figure, the axis of the cylindrical cavity 724 is arranged parallel to the telescopic direction of the arc-bending expansion sleeve 6. When the battery is impacted and collided in a direction parallel to the telescopic direction of the arc-bending expansion sleeve 6, first, the cylindrical iron core 725 compresses the return spring 726, so that the cylindrical iron core 725 contacts the detection contact rod 727. When the cylindrical iron core 725 contacts the detection contact rod 727, the electromagnetic switch air valve 729 is synchronously opened, so that the high-pressure gas in the closed cavity leaks out. At this time, the arc-bending expansion sleeve 6 is softer in the telescopic direction and has a higher buffering effect, buffering subsequent impacts such as collision aftershocks, and improving the protection effect on structures such as the solid electrolyte 4.

[0039] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A solid-state lithium-ion battery with a stable and safe structure, comprising a hard shell (1) and a battery negative electrode (2), a battery positive electrode (3), and a solid electrolyte (4) arranged inside the hard shell (1), characterized in that: An arc-bent telescopic sleeve (6) is arranged on the inner wall surface of the hard shell (1), and a pressure-equalizing side plate (5) is fixedly arranged on the arc-bent telescopic sleeve (6), and the pressure-equalizing side plate (5), the arc-bent telescopic sleeve (6) and the hard shell (1) cooperate to form a closed cavity; when the air pressure in the closed cavity changes, the contact pressure between the battery negative electrode (2), the battery positive electrode (3) and the solid electrolyte (4) can be changed through the pressure-equalizing side plate (5); a bottom clamping cavity (7) is opened at the bottom of the hard shell (1), and a pressure regulating structure is arranged in the bottom clamping cavity (7), and the pressure regulating structure can adjust the air pressure in the closed cavity formed by the pressure-equalizing side plate (5), the arc-bent telescopic sleeve (6) and the hard shell (1).

2. A solid-state lithium-ion battery with a stable and safe structure according to claim 1, characterized in that: The voltage regulating structure comprises an annular hanging eave (701), a stator coil (702) and a permanent magnet rotor ring (703); the annular hanging eave (701) is fixedly arranged on the inner upper surface of the bottom clamping cavity (7); the stator coil (702) is fixedly arranged in the annular hanging eave (701); the permanent magnet rotor ring (703) is arranged in the permanent magnet rotor ring (703); and the stator coil (702) can drive the permanent magnet rotor ring (703) to rotate after an automatic commutation current is passed through it.

3. A solid-state lithium-ion battery with a stable and safe structure according to claim 2, characterized in that: A rotor inner disk (704) is fixedly arranged at the center position of the permanent magnet rotor ring (703), an inner disk upper shaft (705) is fixedly arranged on the upper surface of the rotor inner disk (704), a rotation limiting sleeve (706) is fixedly arranged at the inner upper surface position of the bottom clamping cavity (7), and the inner disk upper shaft (705) is rotationally limited and inserted into the rotation limiting sleeve (706).

4. A solid-state lithium-ion battery with a stable and safe structure according to claim 3, characterized in that: A driving pinion (707) is fixedly provided on the lower surface of the rotor inner disk (704), a large gear ring (708) is meshed with the outside of the driving pinion (707), a central worm (709) is fixedly provided at the center of the large gear ring (708), and a matching worm wheel (710) is meshed with the outside of the central worm (709).

5. A solid-state lithium-ion battery with a stable and safe structure according to claim 4, characterized in that: A limited short shaft (711) is fixedly provided on one side of the mating worm wheel (710), a short shaft limit plate (712) is provided on the outer limit sleeve of the limited short shaft (711), and the short shaft limit plate (712) is fixedly mounted on the inner wall surface of the bottom clamping cavity (7), and a screw rod (713) is coaxially fixedly provided on the other side of the mating worm wheel (710), a telescopic square tube (714) is provided on the outside of the screw rod (713), a screw rod matching portion (715) is fixedly provided on the inside of the telescopic square tube (714), and the screw rod (713) is spirally matched with the screw rod matching portion (715).

6. A solid-state lithium-ion battery with a stable and safe structure according to claim 5, characterized in that: The telescopic square tube (714) is externally sleeved with a square tube outer sleeve (716), and the square tube outer sleeve (716) is fixedly mounted on the inner wall surface of the bottom clamping cavity (7), and when the screw rod (713) rotates, it can drive the telescopic square tube (714) to move along the axial direction of the screw rod (713).

7. A solid-state lithium-ion battery with a stable and safe structure according to claim 6, characterized in that: A pressure-changing cavity (717) is fixedly provided on the inner wall surface of the bottom clamping cavity (7), a pressure-changing piston (718) is provided in the pressure-changing cavity (717), the pressure-changing piston (718) is in airtight contact with the pressure-changing cavity (717), the pressure-changing piston (718) is fixedly installed on the telescopic square tube (714), and the movement of the telescopic square tube (714) drives the pressure-changing piston (718) to move, and a convex ridge (719) is fixedly provided on the inner wall surface of the bottom clamping cavity (7).

8. A solid-state lithium-ion battery with a stable and safe structure according to claim 7, characterized in that: The convex rib (719) is provided with a rib inner cavity (720), and the rib inner cavity (720) is connected to a closed cavity formed by the pressure-equalizing side plate (5), the arc-bent telescopic sleeve (6) and the hard outer shell (1). A connecting pipe (721) is fixedly provided on the inner wall surface of the bottom clamping cavity (7), and the pressure-changing cavity (717) is connected to the rib inner cavity (720) via the connecting pipe (721). An air pressure sensor (722) for detecting the air pressure inside the rib inner cavity (720) is installed on the convex rib (719).

9. A solid-state lithium-ion battery with a stable and safe structure according to claim 8, characterized in that: A detection attachment rib (723) is fixedly arranged on the convex rib strip (719), a cylindrical cavity (724) is provided in the detection attachment rib (723), the axis of the cylindrical cavity (724) is parallel to the axis of the arc bending telescopic sleeve (6), a cylindrical iron core (725) is provided in the cylindrical cavity (724), a reset spring (726) and a detection feeler (727) are respectively provided on both sides of the cylindrical iron core (725), and the cylindrical iron core (725) is elastically supported by the reset spring (726). Located in the middle of the cylindrical cavity (724), the two ends of the cylindrical cavity (724) are respectively penetrated by breathing slots (728) facing outward, and an electromagnetic switch air valve (729) is installed on the convex rib (719). When the electromagnetic switch air valve (729) is opened, the inner cavity (720) of the rib is connected to the outside atmosphere through the electromagnetic switch air valve (729); when the cylindrical iron core (725) contacts the detection feeler (727), the electromagnetic switch air valve (729) is controlled to open.

10. A process for preparing a solid-state lithium-ion battery with a stable and safe structure according to any one of claims 1 to 9, characterized in that: The process includes the following steps: Step 1, weighing a positive electrode active material, a conductive agent and a binder, dissolving the conductive agent and the binder in an organic solvent to form a glue solution; adding the positive electrode active material to the glue solution, mixing evenly to form a positive electrode slurry, coating the positive electrode slurry on an aluminum foil current collector, rolling and cutting into a suitable size after drying, to obtain a battery positive electrode (3); Step 2, selecting a solid electrolyte material and pre-treating it, and preparing a solid electrolyte (4) by pulsed laser deposition; Step 3, weighing the negative electrode active material, the conductive agent and the binder, dissolving the binder in water to prepare a glue solution, adding the conductive agent and the active material to stir to prepare a negative electrode slurry, coating the negative electrode slurry on a copper foil current collector, drying, rolling and cutting to obtain a battery negative electrode (2); Step 4: stacking the battery positive electrode (3), the solid electrolyte (4) and the battery negative electrode (2) in order, coating the interface modifier between the stacked surfaces, hot pressing to make the layers fit together, and then encapsulating them in a hard shell (1) to complete the preparation; Step 5: Connect the battery test equipment and perform the first charge and discharge formation with low current density to activate the electrochemically active substances.

Images