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CN-116895856-B - Battery management device and method for manufacturing battery management device

CN116895856BCN 116895856 BCN116895856 BCN 116895856BCN-116895856-B

Abstract

The invention provides a battery management device and a manufacturing method of the battery management device, which can restrain unexpected fuse from fusing with a simpler structure. The battery management device includes a battery cell, a substrate having a wiring, a fuse connected to the wiring, a resistor for generating electric heat in the vicinity of the fuse, a field effect transistor for opening and closing a current path of the resistor, a protection IC for controlling an operation of the field effect transistor, a first extension extending from the wiring between the protection IC and a gate of the field effect transistor, and a second extension extending from the wiring connected to a source of the field effect transistor, wherein an end of the first extension and an end of the second extension have exposed portions on which a protective film of the substrate is not formed, and an end of the first extension and an end of the second extension are not connected.

Inventors

  • Saito Kuizhi

Assignees

  • 株式会社村田制作所

Dates

Publication Date
20260508
Application Date
20230224
Priority Date
20220330

Claims (6)

  1. 1. A battery management apparatus, comprising: A battery unit; a substrate on which a wiring connected to the battery cell is formed; a fuse connected to the wiring; a resistor disposed in the vicinity of the fuse to generate electric heat; A field effect transistor configured to be able to switch conduction and non-conduction of a current from the battery cell with respect to the resistor; A circuit connected to the battery cell, for supplying an operating voltage for establishing the conduction between the source and the drain of the field-effect transistor to the gate of the field-effect transistor in response to an abnormality in the output voltage of the battery cell; a first extension extending from a wiring between the circuit and the gate, and A second extension portion extending from a wiring connected to the source electrode, The end of the first extension part and the end of the second extension part are provided with exposed parts on which the protective film of the substrate is not formed, The end of the first extension is not connected to the end of the second extension.
  2. 2. The battery management device of claim 1 wherein, A part of the wiring is exposed from a cross section of an end portion of the first extension portion and an end portion of the second extension portion.
  3. 3. The battery management device of claim 2, wherein, The exposed portion is formed by an optical action.
  4. 4. The battery management device of claim 2, wherein, The exposed portion is formed by cutting.
  5. 5. The battery management device of claim 1 wherein, The bonding metal is exposed at least one of the end of the first extension portion and the end of the second extension portion.
  6. 6. A method of manufacturing a battery management device, comprising: In the first step of the process, A wiring connecting the battery cells is formed, A fuse connected to the wiring, a resistor arranged in the vicinity of the fuse to generate electric heat, a field effect transistor provided so as to be capable of switching between conduction and non-conduction of a current from the battery cell with respect to the resistor, and a circuit connected to the battery cell to supply an operating voltage for establishing the conduction between a source and a drain of the field effect transistor to a gate of the field effect transistor in response to an abnormality in an output voltage of the battery cell, Connecting the substrate of the field effect transistor with the battery unit, and And a second step of performing processing for making a conductive path between a gate and a source of the field effect transistor that is conductive on the substrate non-conductive.

Description

Battery management device and method for manufacturing battery management device Technical Field The present invention relates to a battery management device and a method for manufacturing the battery management device. Background If the battery voltage abnormally rises due to overcharge of the secondary battery or the like, the battery may fire, and therefore, in order to prevent this, a fuse is generally provided on a current path connecting the battery. Here, an unexpected abnormal voltage may be generated due to an error in the mounting step of the battery, and the fuse may be blown. Patent document 1 describes a configuration in which two switches are provided in a current supply path to a resistance heating element that fuses a fuse provided on a substrate that connects a plurality of batteries. Patent document 1 discloses an abnormality detection circuit that detects a voltage abnormality of a battery and turns on one of the two switches, and an operation confirmation circuit that turns on the other of the two switches when detecting a current flowing when a plurality of batteries are normally connected. According to the structure of patent document 1, before a plurality of batteries are normally connected, the other of the two switches is opened, so even if an abnormal voltage is applied due to an assembly error, the fuse is not blown. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2017-027798 Disclosure of Invention However, in the structure of patent document 1, both the operation confirmation circuit and the other of the two switches on the current supply path to the resistance heating element that fuses are provided only for suppressing an abnormal voltage setting due to an assembly error, and it is inevitable that the cost is increased due to these components. In the structure of patent document 1, it is necessary to secure a substrate space for providing these components, and therefore, the structure cannot be adopted in which the substrate space cannot be secured. The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a battery management device and a method for manufacturing the battery management device, which can suppress unexpected fuse blowing with a simpler structure. A battery management device according to one aspect of the present invention includes a battery cell, a substrate that forms a wiring connected to the battery cell, a fuse connected to the wiring, a resistor disposed in the vicinity of the fuse and generating electric heat, a field effect transistor provided so as to be capable of switching between conduction and non-conduction of a current from the battery cell with respect to the resistor, a circuit connected to the battery cell, a circuit that supplies an operating voltage for establishing the conduction between a source and a drain of the field effect transistor to a gate of the field effect transistor in response to an abnormality in an output voltage of the battery cell, a first extension extending from the wiring between the circuit and the gate, and a second extension extending from the wiring connected to the source, wherein an end of the first extension and an end of the second extension have exposed portions where a protective film of the substrate is not formed, and an end of the first extension and an end of the second extension are not connected. A method for manufacturing a battery management device according to another aspect of the present invention includes a first step of forming a wiring for connecting a battery cell, a fuse connected to the wiring, a resistor disposed in the vicinity of the fuse for generating electric heat, a field effect transistor provided so as to be capable of switching between conduction and non-conduction of a current from the battery cell with respect to the resistor, and a circuit connected to the battery cell, wherein an operation voltage for establishing the conduction between a source and a drain of the field effect transistor is supplied to a gate of the field effect transistor in response to an abnormality in an output voltage of the battery cell, and finally, a substrate for conducting between the gate and the source of the field effect transistor is connected to the battery cell, and a second step of performing processing of making a conduction path between the gate and the source of the field effect transistor that is conducted on the substrate be non-conductive. According to the present invention, unexpected fuse blowing can be suppressed with a simpler structure. Drawings Fig. 1 is a circuit diagram showing a main configuration of a battery management device. Fig. 2 is a circuit diagram showing a main configuration of the battery management device. Fig. 3 is a schematic diagram showing an example of a circuit mounting structure in the vicinity of a field effect transistor in a state before co