Thermal management benefits for EV battery

Electric vehicle batteries are continually evolving to last longer, provide better operational performance and guarantee optimal safety. The battery requires reliable thermal management to meet these ever-increasing demands.

Since temperature plays a huge role in battery longevity and operational performance, the battery must maintain a proper temperature range. If the temperature is too low, the capacity of the battery can decrease. Conversely, if the temperature is too high, degradation of the battery can occur, which can reduce the life cycle but can also cause safety risks that can have catastrophic consequences. Keeping the temperature constant and evenly distributed is advisable, but this can be challenging as excessive heat can occur for different reasons, such as overcharging, rapid discharging or environmental factors.

The ongoing optimisation of batteries also plays a role. With the goal to increase battery performance and reduce weight, battery cells have a higher energy density that results in more heat generated inside a smaller space. Therefore each battery must be designed with a thermal management system that protects the battery from overheating and guides the heat safely away from the critical components.

Each battery contains a Battery Management System (BMS) and a cooling circuit. While the BMS and cooling circuit control and manage the temperature inside the battery, the presence of thermal conductive pastes or gap fillers efficiently dissipates heat away from the battery to maintain the ideal operating temperature. 

During the battery pack assembly, large volumes of thermal interface materials (TIMs), also known as gap fillers, are dispensed between the cooling circuit and the battery modules/cells. TIMs contain highly abrasive fillers with thermally conductive characteristics, allowing heat to be dissipated away from the battery cells/module towards the cooling circuit.

Thermally conductive interface materials are highly viscous and contain highly abrasive fillers that lead to excessive wear on wetted parts of the equipment such as pumps, shafts, or seals. Traditional dispense systems do not meet the production durability requirements, which leads to increased downtime and equipment maintenance costs. 

Correctly applying thermal materials can be challenging and requires proper attention. These pastes are often two-component materials that necessitate a precise, on-ratio dispense. Because applications also require large volumes of material, it is crucial to dispense the appropriate and even amounts of material to avoid air gaps or overflow. 

At Graco, we have extensive experience working with highly viscous and highly abrasive materials. We have designed our dispense systems with abrasive-resistant components to withstand the harshest conditions and provide the precision dispense required to meet these demanding applications. 

The Graco Advantage

• Proper distribution of material for low or high flow applications
• An accurate and repeatable dispense
• Data downloads – process data and job logs
• Easy integration into automation equipment 
• World-class service and support