Battery Cell Solder Joint Spacing for Uniform Current Flow

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The uneven distribution of solder joints in a cylindrical battery causes non-uniform current reception on electrode sheets, leading to irregular current flow and increased energy loss.

Innovation Solution

The solder joints are arranged at equal arc distances along the winding direction of the wound body, forming a uniform distribution on the full electrode tabs, ensuring uniform current transmission to the electrode sheets.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If full electrode tabs are soldered through laser soldering forming multiple solder joints in a V-shape or Chinese character pattern, then the electrode tabs are connected to the electrode sheets, but the current distribution on the electrode sheets becomes non-uniform

Engineering Contradiction:
Improvecurrent distribution uniformityVSAvoidenergy loss
Core Design Contradiction:
ReliabilityVSLoss of energy

Solution Approach 1:

The patent segments the soldering process into multiple discrete solder joints arranged at equal arc distances along the winding direction, rather than forming continuous V-shaped or Chinese character patterns. This segmentation distributes the current entry points uniformly across the electrode sheets, preventing current concentration in specific areas and improving overall current distribution uniformity while reducing energy loss.

Inventive Principle:
Principle #1Segmentation

2Reliability

If multiple solder joints are arranged at equal arc distances along the winding direction, then current transmission uniformity is improved, but the manufacturing complexity increases

Engineering Contradiction:
Improvecurrent transmission uniformityVSAvoidsoldering process complexity
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent changes the arrangement parameters of the solder joints from conventional V-shaped or Chinese character patterns to a uniform distribution along the winding direction at equal arc distances. This parameter change simplifies the design criteria while achieving uniform current transmission, as the equal arc distance arrangement provides a clear, measurable specification that guides the soldering process.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent performs preliminary simulation and calculation to determine the optimal soldering trajectory and positions before actual manufacturing. By pre-calculating the equal arc distance intervals and soldering paths based on winding parameters, the complex uniform distribution requirement is transformed into a straightforward manufacturing guideline, reducing on-site decision-making complexity.

Inventive Principle:
Principle #10Preliminary action

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This arrangement enhances uniformity of current reception by the electrode sheets, reducing the number of additional current paths and minimizing energy loss.

Implementation Method 1

current collecting parts, soldered to sides, facing away from the wound body, of the full electrode tabs to form multiple solder joints

Methodology Applied
Scientific EffectSoldering: Soldering

Data Source

PatentEP4664663A1Soldering structure and soldering method for battery cell, and battery
Publication Date: 2025.12.17 HUIZHOU EVE POWER CO LTD
  • EP4664663A1 patent drawingFigure 1
  • EP4664663A1 patent drawingFigure 2
  • EP4664663A1 patent drawingFigure 3~4

AI summary

A soldering structure and a soldering method for a battery cell, and a battery are provided, relating to the field of battery technology. The soldering structure for the battery cell includes a wound body; full electrode tabs, formed at ends of the wound body; and current collecting parts, soldered to sides, facing away from the wound body, of the full electrode tabs to form multiple solder joints; in which the multiple solder joints are arranged at equal arc distances along a winding direction of the wound body. The multiple solder joints are arranged at equal arc distances along the winding direction of the wound body, so that the solder joints can be uniformly distributed on the full electrode tabs along the winding direction, and a current can be uniformly transmitted into the wound body through the full electrode tabs, reducing the current loss.