Condition Monitoring of batteries

© Fraunhofer IGD

Motivation

Since introduction to the market in the 1990’s, lithium-ion batteries have been applied in many fields such as every-day used, small electronics (smartphones, laptops), and much more specialized applications, for instance, electric vehicles or autonomous underwater vehicles (AOVs). Despite the many advantages of lithium-ion batteries, which give them an advantage on the market, they also have several limitations, which apply to each battery, regardless of chemistry or design. The biggest limitation is the battery degradation over a number of charge/discharge cycles, what can significantly reduce the battery lifetime, what in turn may cause serious effects for the user. Therefore, the monitoring of batteries is extremely crucial to provide safe and effective operation of batteries.

Short description of the project

SOT working group in the cooperation with Fraunhofer IKTS presents novel methods in the battery condition monitoring, targeted for underwater applications – ROVs, AOVs, underwater energy storage systems. Our techniques are based on the use of piezoelectric transducers and generated by them ultrasonic waves which propagate in the battery and interact with its components. Our flagship technology – Guided Waves Battery Monitoring takes advantage on the fact, that during charge/discharge cycles and during the battery degradation, the mechanical properties of the battery’s constituents are changing, what influences the propagation of Guided Waves. Therefore, the correlation between wave parameters and mechanical properties of the battery is used for determination of the battery State of Charge (SoC) and State of Health (SoH).

Fields of application

Our techniques, applicable for any kind of battery design and chemistry, provides:

  •  accurate SoC and SoH determination
  •  increased safety of operation
  •  longer time underwater – cost reduction
  •  longer battery lifespan
  •  increased stability and reliability
  •  forecast of the battery degradation
 

Smart Ocean Technologies research group