All-solid-state battery system

Abstract

To provide an all-solid battery system that can suppress output and input restrictions when traveling on routes with high input / output performance.SOLUTION: An all-solid battery system installed in a mobile object includes a concentration unevenness detection mechanism that detects Li ion concentration unevenness in the electrode thickness direction of an all-solid battery, an information acquisition unit that acquires information on a travel route of the mobile object, and a charge / discharge control unit of the all-solid battery, and when the information acquisition unit determines to travel on a route with high input performance, the charge / discharge control unit provides a discharge history before entering the route with high input performance, and when the information acquisition unit determines that the information acquisition unit travels on a route having high output performance, the charging / discharging control unit provides a charging history before entering the route having high output performance.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an all-solid-state battery system. [Background technology]

[0002] In recent years, with the rapid spread of information-related devices and communication devices such as personal computers, video cameras, and mobile phones, the development of batteries to be used as power sources for these devices has become important. In the automobile industry, too, development of high-output, high-capacity batteries for electric vehicles or hybrid vehicles is underway.

[0003] Patent Document 1 discloses an all-solid-state secondary battery system having a charging rate control device that estimates the distribution state of lithium in a negative electrode active material layer and controls the maximum charging rate of the all-solid-state secondary battery according to the estimated distribution state. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-161300 A Summary of the Invention [Problem to be solved by the invention]

[0005] When a mobile vehicle is equipped with an all-solid-state battery system as a power source, if input and output are controlled solely according to the distribution state of lithium, output and input restrictions may be imposed when traveling along a route with high input / output performance, and the vehicle may not be able to perform the actions desired by the user.

[0006] The present disclosure has been made in consideration of the above-described circumstances, and has a main object to provide an all-solid-state battery system that can suppress output limitations and input limitations when traveling along a route with high input / output performance. [Means for solving the problem]

[0007] The all-solid-state battery system of the present disclosure is an all-solid-state battery system mounted on a moving body, A concentration unevenness detection mechanism for detecting Li-ion concentration unevenness in the electrode thickness direction of the all-solid-state battery; An information acquisition unit that acquires information on a moving route of the moving object; A charge / discharge control unit for the all-solid-state battery, When the information acquisition unit determines that the vehicle is to travel along a route having high input performance, the charge / discharge control unit provides a discharge history before entering the route having high input performance, When the information acquisition unit determines that the vehicle is to travel along a route having high output performance, the charge / discharge control unit provides a charging history before entering the route having high output performance. Effect of the Invention

[0008] The present disclosure can provide an all-solid-state battery system that can suppress output limitations and input limitations when traveling along a route with high input / output performance. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a flowchart showing an example of control of the all-solid-state battery system of the present disclosure mounted on a vehicle. [Diagram 2] FIG. 2 is a diagram showing an example of the behavior of the voltage and current of an all-solid-state battery when a vehicle is traveling along a route having high output performance in the cases where the control of the present disclosure is performed and where the control is not performed. [Diagram 3] FIG. 3 is a diagram showing an example of the behavior of the Li-ion concentration distribution in an all-solid-state battery while a vehicle is traveling along a route having high output performance when the control of the present disclosure is performed and when the control is not performed. [Figure 4] FIG. 4 is a diagram showing an example of the behavior of the voltage and current of an all-solid-state battery when a vehicle is traveling along a route having high input performance in the cases where the control of the present disclosure is performed and where the control is not performed. [Diagram 5]FIG. 5 is a diagram showing an example of the behavior of the Li-ion concentration distribution in the all-solid-state battery while the vehicle is traveling along a route having high input performance when the control of the present disclosure is performed and when it is not performed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, embodiments of the present disclosure will be described. Note that matters other than those specifically mentioned in this specification and necessary for implementing the present disclosure (for example, the general configuration and manufacturing process of an all-solid-state battery system that does not characterize the present disclosure) can be understood as design matters of a person skilled in the art based on the prior art in the field. The present disclosure can be implemented based on the contents disclosed in this specification and the technical common sense in the field. In this specification, the use of "to" indicating a numerical range means that the numerical values ​​before and after it are included as the lower limit and upper limit. Furthermore, any combination of upper and lower limits in a numerical range can be used.

[0011] The all-solid-state battery system of the present disclosure is an all-solid-state battery system mounted on a moving body, A concentration unevenness detection mechanism for detecting Li-ion concentration unevenness in the electrode thickness direction of the all-solid-state battery; An information acquisition unit that acquires information on a moving route of the moving object; A charge / discharge control unit for the all-solid-state battery, When the information acquisition unit determines that the vehicle is to travel along a route having high input performance, the charge / discharge control unit provides a discharge history before entering the route having high input performance, When the information acquisition unit determines that the vehicle is to travel along a route having high output performance, the charge / discharge control unit provides a charging history before entering the route having high output performance.

[0012] If the history before charging and discharging (the state of uneven Li-ion concentration in the thickness direction of each positive and negative electrode) changes, the battery resistance during charging and discharging will differ even at the same SOC, and there are cases in which the system upper and lower voltage limits will be reached, restricting input and output. According to the present disclosure, by providing a charge / discharge history before entering a route with high input / output performance, it is possible to suppress output and input limitations when traveling along a route with high input / output performance. Being able to travel a specified route without input / output limitations leads to improved fuel efficiency and improved marketability.

[0013] Examples of the mobile body include vehicles such as trains, ships, aircraft, hybrid electric vehicles (HEVs), plug-in hybrid electric vehicles (PHEVs), electric vehicles (BEVs), gasoline-powered vehicles, and diesel-powered vehicles. In particular, the mobile body may be a hybrid electric vehicle, a plug-in hybrid electric vehicle, or an electric vehicle.

[0014] The all-solid-state battery system includes a concentration unevenness detection mechanism, an information acquisition unit, and a charge / discharge control unit.

[0015] The concentration unevenness detection mechanism detects Li ion concentration unevenness in the electrode thickness direction of the all-solid-state battery. The concentration unevenness detection mechanism may be the lithium distribution state estimation device described in Patent Document 1 or the like.

[0016] The all-solid-state battery of the present disclosure may include a positive electrode, a solid electrolyte layer, and a negative electrode. The positive electrode has a positive electrode layer, and optionally a positive electrode current collector. The negative electrode has a negative electrode layer, and optionally a negative electrode current collector.

[0017] The all-solid-state battery may, as necessary, include an exterior body that houses a laminate including a positive electrode current collector, a positive electrode layer, a solid electrolyte layer, a negative electrode layer, and a negative electrode current collector in this order, and a restraining member and the like. The material of the exterior body is not particularly limited as long as it is stable with respect to the solid electrolyte, and examples of the material include polypropylene, polyethylene, and resins such as acrylic resin. The restraining member may be any known member usable as a battery restraining member as long as it can apply a restraining pressure in the stacking direction to the laminate. For example, a restraining member having plate-shaped parts that sandwich both surfaces of the laminate, a rod-shaped part that connects the two plate-shaped parts, and an adjustment part that is connected to the rod-shaped part and adjusts the restraining pressure by a screw structure or the like can be used. The adjustment part can apply a desired restraining pressure to the laminate. The restraining pressure is not particularly limited, but may be, for example, 0.1 MPa or more, 1 MPa or more, or 5 MPa or more. By increasing the restraining pressure, there is an advantage that it is easier to improve the contact between the layers. On the other hand, the restraining pressure may be, for example, 100 MPa or less, 50 MPa or less, or 20 MPa or less. If the restraining pressure is too high, the restraining member is required to have high rigidity, and the restraining member may become large.

[0018] The all-solid-state battery may have only one of the laminates described above, or may be formed by laminating a plurality of the laminates. The all-solid-state battery may be an all-solid-state lithium-ion secondary battery or the like. Examples of the shape of the all-solid-state battery include a coin type, a laminate type, a cylindrical type, and a square type.

[0019] In the method for producing an all-solid-state battery of the present disclosure, for example, a solid electrolyte layer is formed by first applying a paste for forming a solid electrolyte layer to a support and drying it. Then, a paste for forming a positive electrode layer containing a positive electrode active material is applied on one side of the solid electrolyte layer and dried to obtain a positive electrode layer. Thereafter, the support is peeled off from the solid electrolyte layer, and a paste for forming an anode layer is applied on the other side of the solid electrolyte layer and dried to form a negative electrode layer. If necessary, a positive electrode current collector may be attached to the side of the positive electrode layer opposite the solid electrolyte layer, and a negative electrode current collector may be attached to the side of the negative electrode layer opposite the solid electrolyte layer to form an all-solid-state battery.

[0020] The information acquisition unit acquires information on a travel route of the mobile object. The information on the travel route of the moving object may be topographical information of the travel route based on connected information such as VICS (registered trademark) and vehicle-to-vehicle communication.

[0021] The charge / discharge control unit controls charging and discharging of the all-solid-state battery.

[0022] The information acquisition unit determines a predetermined route having a high input / output, and the charge / discharge control unit performs control to form a Li-ion concentration distribution in which input / output is not restricted before entering the predetermined route. When the information acquisition unit determines that the vehicle is to travel along a route having high input performance, the charge / discharge control unit provides a discharge history before entering the route having high input performance, When the information acquisition unit determines that the vehicle is to travel along a route having high output performance, the charge / discharge control unit provides a charging history before entering the route having high output performance. The discharge history may be a history of continuous discharge of the required power. The charge history may be a history of continuous charging of the required power. The history of continuous charging and discharging of the required power may be brake regeneration, engine output, auxiliary battery energy, or a combination of these, as long as continuous current can be maintained. An example of a route having high input performance is a downhill route. An example of a route having high output performance is an uphill section.

[0023] The information acquisition unit and the charge / discharge control unit physically include, for example, a processing device such as a CPU (central processing unit), a ROM (read-only memory) that stores control programs and control data processed by the CPU, a storage device such as a RAM (random access memory) that is mainly used as various working areas for control processing, and an input / output interface.

[0024] FIG. 1 is a flowchart showing an example of control of the all-solid-state battery system of the present disclosure mounted on a vehicle. After starting the vehicle (engine ON), the information acquisition unit determines the driving route and the high input / output route through communication. The charge / discharge control unit determines the power required for the high input / output route and performs charge / discharge history monitoring driving. The information acquisition unit determines whether a route having high input / output is a route having high input performance or a route having high output performance. When the information acquisition unit determines that the vehicle will travel along a route with high input performance, the charge / discharge control unit charges the required power as a discharge history before entering the route with high input performance, and then discharges the required power (+ output from driving), and within the route with high input performance, inputs power to the main battery (solid-state battery) and continues driving while monitoring the charge / discharge history. On the other hand, if the information acquisition unit determines that the vehicle will travel along a route with high output performance, the charge / discharge control unit discharges the required power as the charging history before entering the route with high output performance, and then charges the required power (+ input from driving), and within the route with high output performance, outputs from the main battery and continues driving while monitoring the charge / discharge history.

[0025] FIG. 2 is a diagram showing an example of the behavior of the voltage and current of an all-solid-state battery when a vehicle is traveling along a route having high output performance in the cases where the control of the present disclosure is performed and where the control is not performed. When the control of the present disclosure is performed, the voltage of the all-solid-state battery does not reach the lower limit voltage, and the battery output can be maintained. On the other hand, if the control of the present disclosure is not performed, the voltage of the all-solid-state battery will reach the lower limit voltage, and the battery output will decrease.

[0026] FIG. 3 is a diagram showing an example of the behavior of the Li-ion concentration distribution in an all-solid-state battery while a vehicle is traveling along a route having high output performance when the control of the present disclosure is performed and when the control is not performed. When the control of the present disclosure is performed, the ion migration resistance of the all-solid-state battery is low, the voltage does not reach the lower limit voltage, and the battery output can be maintained. On the other hand, if the control of the present disclosure is not performed, the ion migration resistance of the all-solid-state battery is high, and there is a concern that the voltage will reach the lower limit voltage.

[0027] FIG. 4 is a diagram showing an example of the behavior of the voltage and current of an all-solid-state battery when a vehicle is traveling along a route having high input performance in the cases where the control of the present disclosure is performed and where the control is not performed. When the control of the present disclosure is performed, the voltage of the all-solid-state battery does not reach the upper limit voltage, and the battery input can be maintained. On the other hand, if the control of the present disclosure is not performed, the voltage of the all-solid-state battery reaches the upper limit voltage, and the battery input decreases.

[0028] FIG. 5 is a diagram showing an example of the behavior of the Li-ion concentration distribution in the all-solid-state battery while the vehicle is traveling along a route having high input performance when the control of the present disclosure is performed and when it is not performed. When the control of the present disclosure is performed, the ion transfer resistance of the all-solid-state battery is low, the voltage does not reach the upper limit voltage, and the battery input can be maintained. On the other hand, if the control of the present disclosure is not performed, the ion migration resistance of the all-solid-state battery is high, and there is a concern that the voltage will reach the upper limit voltage.

Claims

[Claim 1] An all-solid-state battery system mounted on a moving object, A concentration unevenness detection mechanism for detecting Li ion concentration unevenness in an electrode thickness direction of the all-solid-state battery; An information acquisition unit that acquires information on a moving route of the moving object; A charge / discharge control unit for the all-solid-state battery, When the information acquisition unit determines that the vehicle is to travel along a route having high input performance, the charge / discharge control unit provides charging of a required amount of power and discharging of a required amount of power as a discharge history before entering the route having high input performance, When the information acquisition unit determines that the battery will travel along a route having high output performance, the charge / discharge control unit discharges the required power as a charging history before entering the route having high output performance, and then charges the required power.

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