Lithium Primary Battery Tape Adhesion via Phosphorus Additive

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithium primary batteries face issues where the electrolyte enters gaps under the adhesive material of the tape attached to the negative electrode, leading to reduced adhesive force, peeling of the tape, and impaired function of the lithium negative electrode as a current collector, resulting in decreased battery capacity.

Innovation Solution

A lithium primary battery design incorporating a non-aqueous electrolyte with a phosphorus compound having a POn structure, a tape with a resin base material and adhesive layer, and a specific width range to prevent electrolyte entry and maintain the negative electrode's function as a current collector, ensuring effective suppression of dissolution reactions.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a tape is attached to the negative electrode to suppress dissolution reaction, then the function as current collector is maintained, but the electrolyte enters the gap under the adhesive material causing the tape to peel and float

Engineering Contradiction:

Improvefunction as current collectorVSAvoidadhesive force

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

A gel layer is introduced as an intermediary substance between the adhesive material and the negative electrode. This gel layer acts as a barrier that prevents the electrolyte from penetrating into the gap between the adhesive and the electrode, thereby maintaining adhesive force and preventing tape peeling while allowing the tape to continue suppressing the dissolution reaction of the lithium negative electrode.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The gel layer functions as a thin film barrier that conforms to the interface between the adhesive material and the negative electrode. This flexible film structure effectively seals the gap without rigid constraints, preventing electrolyte infiltration while maintaining the structural integrity and adhesive properties of the tape assembly throughout battery discharge.

Inventive Principle:

Principle #30Flexible shells and thin films

2Reliability

If the tape peels and floats due to electrolyte entry, then the dissolution reaction cannot be suppressed, but the negative electrode function as current collector is impaired

Engineering Contradiction:

Improvedissolution reaction suppressionVSAvoidbattery capacity

Core Design Contradiction:

ReliabilityVSProductivity

Solution Approach 1:

The gel layer serves as a protective intermediary that ensures continuous contact between the tape and the negative electrode throughout discharge. By preventing electrolyte penetration that would cause peeling, the gel layer maintains the tape's position and effectiveness in suppressing dissolution reactions, thereby preserving the negative electrode's current collector function and achieving designed battery capacity.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Stability of the object's composition

If the adhesive force is reduced by electrolyte entry, then the tape peels, but the gap formation allows electrolyte to reach the negative electrode

Engineering Contradiction:

Improveadhesive material stabilityVSAvoidelectrolyte contact with negative electrode

Core Design Contradiction:

Stability of the object's compositionVSObject-affected harmful factors

Solution Approach 1:

The gel layer acts as a dual-function intermediary: it maintains the stability of the adhesive material by preventing electrolyte degradation while simultaneously serving as a physical barrier that blocks electrolyte contact with the negative electrode. This layered structure protects both the adhesive properties and the electrode from harmful electrolyte interaction.

Inventive Principle:

Principle #24Intermediary (Mediator)

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

The solution maintains the negative electrode's function as a current collector throughout discharge, preventing breaks and ensuring the battery achieves its designed capacity, with the phosphorus compound enhancing adhesion and reducing tape floating.

Implementation Method 1

the additive including a phosphorus compound having a POn structure having a phosphorus atom and n oxygen atoms bonded to the phosphorus atom, where n=3 or 4

Methodology Applied

Scientific EffectFilm formation: Deposition (physical)

Implementation Method 2

the tape including a resin base material and an adhesive layer

Methodology Applied

Scientific EffectAdhesion: Adhesive

Implementation Method 3

As the lithium in the negative electrode foil is consumed by discharge

Methodology Applied

Scientific EffectElectrochemical discharge: Battery (electricity)

Data Source

PatentUS20220271406A1Lithium primary battery

Publication Date: 2022.08.25 PANASONIC INTELLECTUAL PROPERTY MANAGEMENT CO LTD

AI summary

A lithium primary battery including a battery case, an electrode group housed in the battery case, and a non-aqueous electrolyte. The non-aqueous electrolyte contains a non-aqueous solvent, a solute, and an additive. The electrode group includes a positive electrode, a negative electrode, and a separator interposed therebetween. The negative electrode includes a metal lithium or lithium alloy foil, and has a shape having a longitudinal direction and a lateral direction, with a long tape attached to at least one principal surface of the negative electrode along the longitudinal direction. The tape includes a resin base material and an adhesive layer, and has a width of 0.5 mm to 3 mm. The additive includes a phosphorus compound having a POn structure having a phosphorus atom and n oxygen atoms bonded to the phosphorus atom, where n=3 or 4.