Battery Development: Construction of battery modules and systems

Our R&D Services in this Field of Work comprise:

  • Formation of battery cells
  • Electrical, electrochemical and thermal characterization of single cells, battery modules and storage systems up to the megawatt scale
  • Development of battery modules and systems
  • Thermal management and cooling systems
  • Development of battery management and energy management systems
  • Safety concepts for battery systems

 

Electrical, electrochemical and thermal characterization of single cells, battery modules and storage systems up to the megawatt scale

Whether it be a single cell, home storage system or a large system for grid support, we draw up the appropriate testing approach according to our client’s needs.  We characterize all types of storage technologies in our battery lab.

Battery Development: Construction of battery modules and systems

For the different technologies, Fraunhofer ISE develops stacks, modules and systems incorporating the required safety concepts for the different applications. Currently our main emphasis is on Li-ion, lead-acid and redox flow battery technologies. The modules are customized to meet the requirements of the cell and the given application. The necessary mechanical stability and reliability are ensured, independent of whether liquid or air is used for cooling the batteries. We can build systems up to the MW /MWh range. Additionally we develop and use thermal, electrical and electrochemical models from the cell to the system level to assist us in our work.  Representative applications for our battery systems are:

  • PV stand-alone systems
  • Home storage systems to increase PV self-consumption as well as provide grid support
  • Large battery storage systems for wind generators and PV power plants
  • Mobile storage systems for portable devices
  • Electric mobility

Thermal Management and Cooling Systems

Thermal management is very important for the safe and reliable operation of battery storage systems and increases the lifetime of the battery cells as well. However, additional energy is required for the cooling system, so that the efficiency is often below the optimum in the practice. For this reason, Fraunhofer ISE develops highly efficient cooling concepts and systems that fulfil the requirements of safety, reliability and lifetime.  The latest simulation software is used to optimize the layout of the cooling system and to determine the optimum operation strategy.  The input parameters for the models are determined and validated with measurements from our battery laboratory. For example, highly precise calorimeters and infrared cameras are used for the thermal investigations and verification.

Battery and Energy Management Systems

In devices and systems, the controls require continuous information about the status of the battery storage. Even for the most advanced battery technologies, the user has no direct information about the internal state of the battery. What is the state-of-charge (SOC)? When should the battery/cell be exchanged? Using models, Fraunhofer ISE can determine the state-of-charge (SOC) and state-of-health (SOH) in real time and inform the battery owner.  Models of aging can be implemented onto the battery management hardware to provide information about how the operation management affects the battery storage lifetime. We develop intelligent charging and operating control strategies that can be easily integrated into the microcontrollers of charge controllers, device controls as well as battery and energy management systems. This enables, for example, the cooling system to be controlled, faults to be diagnosed and any charging devices that are connected to be optimally accessed in order to allow, for example, a battery-safe fast charging procedure.

Electric Safety Concepts

Modern battery systems (e.g., based on Li-ion batteries) require battery management systems to operate safely and ensure that the cells are constantly within an acceptable state. If a fault occurs, then the system should be able to be shut-down at all times. For this case, the interaction between the functional safety of the battery system and the hardware and software is of crucial importance. Fraunhofer ISE provides consultancy services and can draw up an appropriate concept that serves as a basis for the certification of the battery system.