Lithium Ion Battery
A Lithium-Ion (Li-ion) Battery is a rechargeable energy storage device where lithium ions move between electrodes during charge/discharge, offering high energy density but susceptibility to degradation. In reliability engineering, its State of Health (SoH) is defined by capacity fade and impedance increase, modeled via stochastic processes like Wiener or Weibull distributions to predict time-to-failure in CMMS asset tracking.
In shop floor maintenance, Li-ion batteries are tracked via Battery Management System (BMS) data feeds for State of Charge (SoC), SoH, and temperature, enabling predictive maintenance triggers when parameters exceed thresholds like 20–40°C. Maintenance schedules use degradation models accounting for cell dependency in packs, adjusting replacement intervals based on cycling and calendar stress factors rather than fixed time. On-floor tasks include inspecting cooling systems and thermal management integrity to prevent thermal runaway, a critical failure mode.
How does cell dependency in a pack affect reliability modeling for CMMS scheduling?
Cell dependency quantifies how failure of one cell accelerates others; models like the Wiener process account for this to optimize redundant cell configuration and adjust maintenance intervals, preventing underestimation of pack failure risk.
What are the primary degradation mechanisms impacting Li-ion State of Health (SoH)?
The chief modes are loss of lithium inventory (LLI), impedance increase, and loss of electrolyte/active material, driven by cycling and calendar stress, with SEI growth and aluminum pitting as critical chemical causes.
How does BMS mitigate thermal runaway in industrial maintenance?
BMS monitors temperature and current, activating positive temperature coefficient (PTC) devices, vents, and circuit breakers to limit current flow and maintain the 20–40°C range, preventing thermal runaway initiated by mechanical abuse or over-charge.