Battery Module Sensor Fixing via Vertical End Plate Inversion

Solution Overview

Problem

Battery modules in electric vehicles face challenges in securely fixing sensor devices due to expansion and vibration, leading to potential rattling, which can increase module dimensions and weight when attempting to firmly attach them to end plates.

Innovation Solution

A battery module design where a sensor device is fixed to an end plate using a fastening member that extends perpendicular to the laminating direction, with the fastening member's end surface located lower than or equal to the sensor device body, and the mounting surface of the cell laminated body positioned lower than the sensor fixing portion's bottom surface, allowing for reduced module size and weight.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the sensor device is firmly fixed to the end plate using a conventional fixing structure, then the sensor device can be securely fixed and prevented from rattling, but the end plate and battery module increase in dimension and weight

Engineering Contradiction:

Improvefixing reliabilityVSAvoidbattery module weight

Core Design Contradiction:

ReliabilityVSWeight of stationary object

Solution Approach 1:

The sensor fixing portion extends in the perpendicular direction (height direction) from the sensor device body to the end plate, utilizing the vertical dimension for fixation. This allows the fastening member to secure the sensor device firmly while keeping the horizontal dimensions compact, avoiding increases in length and width that would expand the battery module footprint.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

Instead of making the end plate protrude upward to accommodate the sensor device and fastening member, the invention inverts the approach by making the end plate surface lower than the mounting surface of the cell laminated body. The sensor device and fastening member extend upward from this lower end plate surface, achieving secure fixation while maintaining a compact overall structure.

Inventive Principle:

Principle #13The other way round (Inversion)

2Reliability

If the sensor device is firmly fixed to the end plate using a conventional fixing structure, then the sensor device can be securely fixed and prevented from rattling, but the end plate and battery module increase in dimension

Engineering Contradiction:

Improvefixing reliabilityVSAvoidbattery module dimension

Core Design Contradiction:

ReliabilityVSLength of stationary object

Solution Approach 1:

The sensor fixing portion extends in the perpendicular direction (height direction) from the sensor device body to the end plate, utilizing the vertical dimension for fixation. This allows the fastening member to secure the sensor device firmly while keeping the horizontal dimensions compact, avoiding increases in length and width that would expand the battery module footprint.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Solution Approach 2:

Instead of making the end plate protrude upward to accommodate the sensor device and fastening member, the invention inverts the approach by making the end plate surface lower than the mounting surface of the cell laminated body. The sensor device and fastening member extend upward from this lower end plate surface, achieving secure fixation while maintaining a compact overall structure.

Inventive Principle:

Principle #13The other way round (Inversion)

3Measurement precision

If the sensor device is mounted on the cell laminated body surface, then the sensor device can detect cell voltage, but the sensor device may be rattled due to vibration during vehicle travel

Engineering Contradiction:

Improvevoltage detection capabilityVSAvoidsensor device stability

Core Design Contradiction:

Measurement precisionVSReliability

Solution Approach 1:

The sensor fixing portion extends in the perpendicular direction (height direction) from the sensor device body to the end plate, utilizing the vertical dimension for fixation. This allows the fastening member to secure the sensor device firmly while keeping the horizontal dimensions compact, avoiding increases in length and width that would expand the battery module footprint.

Inventive Principle:

Principle #17Another dimension (Dimensionality change)

Data Source

PatentUS11228064B2Battery module and battery unit having a sensor device mounted thereon

Publication Date: 2022.01.18 HONDA MOTOR CO LTD

AI summary

A battery module includes: a cell laminated body; a first and a second end plates which are provided at both end portions of the cell laminated body; and a sensor device which is mounted on a mounting surface and detects the voltage of each cell in the cell laminated body. The sensor device includes: a sensor device body; and a sensor fixing portion which is fixed to the first end plate by a fastening member. In the perpendicular direction, an end surface of the fastening member is located to be lower than or equal to an end surface of the sensor device body, the mounting surface of the cell laminated body is located to be lower than a bottom surface of the sensor fixing portion, and an end surface of the first end plate is located to be lower than the mounting surface of the cell laminated body.