The invention provides an
electricity-heat-capacity
coupling-based reliability evaluation method and device for a multi-level networking
energy storage system, and the method comprises the steps: constructing a
battery electricity-heat-capacity
coupling model which comprises three sub-models, namely an electrical sub-model, a thermal characteristic sub-model and a capacity degradation sub-model, and achieving the dynamic synchronous updating of current, temperature and capacity degradation through the closed-loop
coupling of the three sub-models, key parameters are extracted; constructing an inter-battery
thermal runaway spreading model, calculating
heat transfer through a heat conduction network of a two-dimensional lumped
convection model, and simulating a
thermal runaway spreading path, rate and capacity decline trend in combination with a joint
failure probability model based on a Copula function; the model is embedded into a Monte Carlo
simulation framework, and reliability evaluation is carried out by adopting a'
monomer-
branch-
system 'three-
level structure. According to the method, the high-
magnification working condition
simulation precision is improved through dynamic closed-loop updating, physical transmission and probability driving are considered,
safety control is enhanced, and a global
view angle is provided for
system reliability analysis through a multi-level system.