Optimizing lithium battery systems with CFD simulation to reduce design time and costs

Introduction

Founded in 2011, Forsee Power is a pioneer and global leader in designing and manufacturing smart lithium battery systems for vehicles and other products. The company
is committed to constant innovation by providing high-performance, high-safety and long-life battery systems using a standardized product design approach. This design approach ensures flexibility to meet the customer’s unique requirements.

The company’s commitment to innovation extends to optimizing heat dissipation, a significant challenge in lithium battery systems. The company realized it needed to move beyond 1D simulation and studying data in spreadsheets. To do this, Forsee Power teamed up with Siemens Digital Industries Software and integrated Simcenter™ STAR-CCM+™ software as a solution, which is part of the Siemens Xcelerator business platform of software,
hardware and services.

Overcoming battery thermal challenges

When it comes to designing battery systems, there are several challenges, namely concerning thermal design and thermal runway control, which are also key factors for evaluating battery pack safety performance. Forsee Power needs to accurately obtain the thermal design performance of the entire battery pack based on single-core thermal parameters, which the core design enterprise provides at an early design stage. Additionally, the company needed
to avoid finding problems in later experiments or further along in the design stage.

Their previous process often failed to reflect battery heating details. Without adequate details about the battery’s local hot spots, it could lead to the entire battery pack’s cooling system experiencing thermal failure.

Additionally, with this process, it was impossible to conduct thermal testing without a physical prototype in the earlier design stages. Once a problem occurred, it was typically later in the design process, increasing the experimental and time costs due to modifying an already-made design.

To overcome these challenges, Forsee Power knew they needed a simulation solution to catch thermal issues early in the design process.

Forsee Power specializes in the design and manufacturing of intelligent battery systems. They firmly
believe that innovative battery solutions are pivotal for a successful and sustainable energy transition, optimizing the life cycle of smart mobility and devices worldwide.

Using simulations for battery thermal management

Battery manufacturing companies widely use simulation software for battery pack thermal management. After a simulation verifies its parameters and solutions, the engineer can extend the simulation to verify product performance and reduce the number of rounds the experiment undergoes.

“Using Simcenter STAR-CCM+, we could accurately obtain thermal design performance early in the design stage,” says Kinny Ruan, mechanical engineer at Forsee Power.

Due to the computer-aided design (CAD) interface in Simcenter STAR-CCM+, Forsee Power engineers could directly import designs into the battery pack model. Using the core heating data the design team provides, the software simulates and verifies the component’s heat dissipation efficiency, such as cooling channels and fans. This process can replace most traditional and physical experiments, streamlining the overall design phase.

A key breakthrough lies in obtaining detailed 3D temperature distribution data of the battery pack under cycle conditions using simulation. By leveraging Simcenter STAR-CCM+, research and development (R&D) engineers can adjust and make design choices based on a customer’s needs, then quickly obtain the battery pack’s heat dissipation performance. This
process reduced R&D cycles and their associated costs.

“By handing over computing tasks to the Simcenter software, engineers could focus more on building design ideas and defining boundary conditions, truly improving product performance,” says Ken Yan, simulation engineer at Forsee Power.

Additionally, Forsee Power’s smart battery systems significantly contribute to improving mobility. By creating custom variants of standardized products, the company can meet requirements for a wide variety of application scenarios. There is no one-size-fits-all mentality; each client receives a versatile and reliable solution.

Utilizing Simcenter STAR-CCM+, engineers can precisely assess thermal design performance and identify local hot spots in the battery. This enables the optimization of the battery pack’s cooling system for optimal performance.

Applying CFD simulation to verify performance

To determine the success or failure of a product, it is important to keep its specific product development details in mind since it undergoes repeated modifications throughout the design and development process. For this, the company needed a solution; however, there were two main concerns for applying computational fluid dynamics (CFD) simulation. First was ensuring the simulation’s accuracy, and second was the simulation’s efficiency.

When applying this tool to their compact, modular, air-cooled battery, PULSE 0.5, engineers could verify its accuracy in an extreme environment at 40° Celsius. By benchmarking the experimental and simulation results, the feedback simulation and measured trends were consistent, with a simulation monitoring temperature error within 5 percent. The product’s measured high and low temperature positions were carefully displayed by the software, clearly showing their achievement in simulating the experiment.

Using Simcenter STAR-CCM+ helped Forsee Power engineers by making the effects of design changes more intuitive. With this 3D fluid thermal simulation tool, engineers could focus on various details and work towards verifying the product’s performance.

With this solution, Forsee Power reduced the frequency of experiments and achieved accurate temperature data for lifecycle simulation.

Forsee Power has validated the simulation results, confirming their accuracy and consistency with experimental test data. The chart illustrates that the thermal simulation data aligns closely with the experimental data, with an error margin of within 5%.

Creating better battery designs

Integrating Simcenter STAR-CCM+ into Forsee Power’s engineering workflow played a pivotal role in accelerating their design process and improving their ability to achieve these more streamlined and cost-efficient outcomes. Leveraging Simcenter STAR-CCM+ has empowered the company to understand and address thermal challenges in battery pack design, leading to enhanced safety and performance.

Forsee Power’s success story exemplifies the transformative impact of Siemens’ engineering software in overcoming complex challenges in lithium battery system development. As the company continues to optimize product design and performance, their commitment to innovation and reliability in the smart battery systems industry remains unwavering.

In 2022, Forsee Power unveiled the high-power PULSE 0.5 battery, designed to cater to the off-highway market, including applications in agriculture, industry, forestry, mining, forklifts, excavators, and more.