Meaning
Mathematical expression that models the spatial distribution of temperature changes across a physical body in response to localized heat sources. Incorporating a thermal spatial transfer kernel into real-time pack estimators enables rapid temperature predictions without heavy finite element calculations. The function converts localized heat generation into a distributed temperature field.
Mathematical Construction
Green’s functions or analytical transfer functions are used to relate the heat source to the temperature profile. In these models, the thermal spatial transfer kernel is pre-computed based on the geometric and thermal properties of the cell. This pre-computation allows the real-time algorithm to solve the thermal equations using simple convolution operations, which drastically reduces the number of mathematical operations that the processor must perform.
Diffusion Simulation
Thermal diffusion is simulated by applying the kernel to the calculated heat generation rate at each time step. Utilizing the thermal spatial transfer kernel allows the battery management system to predict the internal temperature of the cell, which is difficult to measure directly. This simulation is highly accurate for both transient and steady-state conditions.
Realtime Integration
Run-time performance is high because the kernel method avoids the need for iterative numerical solvers. Implementing the thermal spatial transfer kernel on a microchip allows the safety system to respond to thermal runaway risks within milliseconds. This rapid response is critical for triggering cooling systems before the cell reaches a critical temperature.
