Battery Protective Bottom Plate Sandwich Structure

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing battery pack bottom protection structures have insufficient impact resistance and are prone to connection failures under vibration conditions, leading to surface damage and electrolyte leakage.

Innovation Solution

A battery protection bottom plate comprising an upper fiber reinforced resin layer, a metal plate, and a lower fiber reinforced resin layer, where the metal plate is sandwiched between the resin layers, enhancing corrosion resistance, impact resistance, and stiffness without the need for additional punching.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If a flat steel plate is used for battery pack bottom protection, then the structure is simple and easy to manufacture, but the overall stiffness is poor and impact resistance is insufficient

Engineering Contradiction:
Improveease of manufactureVSAvoidimpact resistance
Core Design Contradiction:
Ease of manufactureVSStrength

Solution Approach 1:

The patent applies composite materials by combining fiber reinforced resin layers with a metal plate to create a sandwich structure. This composite construction provides both the necessary impact resistance and stiffness while maintaining manufacturing feasibility, resolving the contradiction between ease of manufacture and strength.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent transitions from a two-dimensional flat steel plate to a three-dimensional sandwich structure with upper and lower fiber reinforced resin layers enclosing a metal plate. This dimensional change significantly improves stiffness and impact resistance without complicating the manufacturing process.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Strength

If a steel plate is punched to improve stiffness, then the overall stiffness increases, but production efficiency decreases due to difficulty in punching high-strength steel plate

Engineering Contradiction:
Improveoverall stiffnessVSAvoidproduction efficiency
Core Design Contradiction:
StrengthVSProductivity

Solution Approach 1:

The sandwich composite structure achieves the required stiffness without punching the metal plate. The fiber reinforced resin layers provide the necessary structural reinforcement, eliminating the need for difficult punching operations on high-strength steel and thereby maintaining high production efficiency.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The structure is segmented into distinct functional layers: upper fiber reinforced resin layer, metal plate, and lower fiber reinforced resin layer. This segmentation allows each layer to contribute its specific properties (stiffness, strength, flexibility) without requiring modifications like punching to the metal plate, thus preserving production efficiency.

Inventive Principle:
Principle #1Segmentation

3Reliability

If a steel plate with PVC layer is used for protection, then corrosion resistance is improved, but the PVC layer may drop under impact causing connection failure

Engineering Contradiction:
Improvecorrosion resistanceVSAvoidconnection stability
Core Design Contradiction:
ReliabilityVSStrength

Solution Approach 1:

The sandwich composite structure integrates corrosion protection and impact resistance into a unified design. The fiber reinforced resin layers provide both corrosion resistance and structural integrity, eliminating the need for separate PVC coating that could detach under impact.

Inventive Principle:
Principle #40Composite materials

Solution Approach 2:

The patent merges the corrosion protection function and structural strength function into a single integrated sandwich structure. The fiber reinforced resin layers simultaneously provide corrosion resistance and maintain connection stability under impact, unlike the separate PVC coating approach.

Inventive Principle:
Principle #5Merging (Combining)

Data Source

PatentEP4535530A1Battery protective bottom plate, battery pack composite protective structure, and vehicle
Publication Date: 2025.04.09 BYD CO LTD
  • EP4535530A1 patent drawingFigure 1~2
  • EP4535530A1 patent drawingFigure 3~4
  • EP4535530A1 patent drawingFigure 5~7

AI summary

A battery protective bottom plate, a battery pack composite protective structure and a vehicle. The battery protective bottom plate comprises an upper fiber reinforced resin layer, a metal plate and a lower fiber reinforced resin layer, wherein the metal plate is located between the upper fiber reinforced resin layer and the lower fiber reinforced resin layer, and the following condition is satisfied: (I) 1≤ρ2∗d1+d2+d3/d2ρ2+ρ1∗d1+ρ3∗d3/d1+d3∗σ1∗d1+σ3∗d3/d1+d3σ2≤2.