The Importance of Applying Glue Between Prismatic Battery Cells in ESS

Energy Storage Systems (ESS) play a crucial role in stabilizing power grids, integrating renewable energy, and supporting industrial power needs. Prismatic lithium-ion batteries are widely used in ESS due to their compact design, high energy density, and durability. However, proper assembly is essential to ensure the long-term performance and safety of these battery modules. One key step in the assembly process is applying glue between prismatic battery cells.

Although it may seem like a minor detail, glue plays a vital role in ensuring the stability, safety, and efficiency of the battery pack. This article explores why glue is applied between prismatic battery cells, its key benefits, and how it improves the overall performance of ESS battery packs.

1. Ensuring Structural Stability

Battery modules in an ESS must remain structurally stable over years of operation. Applying glue between prismatic cells helps keep them securely bonded together, ensuring:

• Strong Module Integrity: Prevents individual cells from shifting or separating over time.

• Prevention of Mechanical Failures: Movement or misalignment of cells can lead to internal damage, reducing the battery’s lifespan.

• Enhanced Pack Durability: Proper adhesion reinforces the overall strength of the battery pack, making it more resilient to external forces.

Without glue, the cells could become loose, leading to electrical connection failures or mechanical stress on the battery casing.

2. Shock and Vibration Absorption

ESS battery modules are often used in environments where they may experience vibrations and external shocks, such as in industrial facilities and renewable energy stations. The glue serves as a shock-absorbing buffer, reducing mechanical stress on the cells.

• Minimizes Physical Stress: Protects battery cells from damage due to frequent micro-movements.

• Enhances Longevity: Reduces wear and tear caused by vibrations, preventing premature battery failure.

• Essential for Transport: Battery modules are often transported before installation, and glue prevents movement-related damage.

By stabilizing the cells, glue application improves both short-term handling safety and long-term operational reliability.

3. Improving Thermal Management

Heat management is one of the most critical aspects of ESS battery performance. If individual cells in a module have uneven temperature distribution, it can lead to:

• Reduced efficiency.

• Faster degradation of certain cells.

• Safety risks, such as overheating or thermal runaway.

Many types of glue used in ESS battery manufacturing have thermal conductive properties, which help:

• Dissipate Heat Evenly: Glue spreads heat across the module, preventing localized overheating.

• Improve Cooling Efficiency: Works in combination with heat sinks and cooling systems for better thermal regulation.

• Enhance Battery Lifespan: By keeping cells at an optimal temperature range, glue helps extend the service life of the battery pack.

A well-managed thermal environment leads to more efficient, stable, and safer battery operation.

4. Electrical Insulation and Safety Enhancement

Prismatic battery cells are enclosed in metal casings, which can pose a risk of short circuits if they come into direct contact with each other. Glue application helps mitigate this risk by:

• Providing an Insulating Barrier: Prevents unintended electrical contact between adjacent cells.

• Reducing Short Circuit Risks: A well-insulated module lowers the chance of internal short circuits that could cause failures.

• Preventing Physical Damage to Cells: Glue absorbs minor impacts, reducing the risk of casing deformation.

Battery safety is a top priority in ESS applications, and glue plays a key role in enhancing electrical insulation and operational safety.

5. Simplifying the Assembly Process

During manufacturing, prismatic cells need to be precisely positioned to create a well-aligned, compact module. Glue application helps streamline the assembly process in the following ways:

• Holds Cells in Place: Ensures proper alignment during welding and connection processes.

• Reduces Assembly Errors: Minimizes the chances of misaligned or loosely placed cells.

• Improves Production Efficiency: Enables faster and more accurate module assembly, reducing manufacturing time and cost.

By keeping cells securely positioned, glue contributes to a more efficient and automated manufacturing process, ensuring higher production consistency.

6. Preventing Swelling and Expansion Issues

During charge and discharge cycles, lithium-ion battery cells expand and contract slightly due to electrochemical reactions. If not properly secured, repeated swelling can:

• Cause misalignment in the module.

• Increase mechanical stress on connectors and busbars.

• Lead to long-term structural weakening of the battery pack.

By applying glue, battery expansion is evenly distributed, reducing excessive pressure on individual cells and ensuring long-term module integrity.

7. Selecting the Right Glue for ESS Batteries

Different types of glue are used in ESS battery assembly, each with specific properties:

• Thermal Conductive Glue: Helps with heat dissipation.

• Flexible Glue: Absorbs shocks and vibrations while allowing slight movement.

• Strong Bonding Glue: Ensures maximum structural stability.

The choice of glue depends on the specific ESS application, operational environment, and manufacturer requirements.