Flexoo GmbH, Germany
With BaMoS 2, Flexoo offers a complete battery monitoring solution, including the sensor foils, electronics to gather and process the captured data, and software for live visualization, storage and analysis of the data.
A key parameter for people buying battery energy storage systems is the performance of the battery in terms of power and durability. During the charge and discharge cycle, a battery cell constantly changes its volume and temperature, it “breathes”.
If it is clamped and fixed in place in rigid packaging, with no change in volume possible, it will instead change its pressure and local temperature. Excessive changes in these parameters lead to degradation and reduced battery lifetime. By monitoring these parameters, pressure and temperature inside the battery, we can make sure that they stay in a safe range and therefore prolong the lifetime of batteries. We propose a solution to monitor pressure and temperature inside BESS battery packs and created a wireless demonstrator to showcase our solution.
Functionality
In our demonstrator, dedicated array of twelve pressure or temperature-sensors are placed between the cells of BESS batteries. Pressure and temperature variations are measured locally.
Pressure sensor arrays are based on piezoresistive pressure sensors printed on a roll-to-roll printed machine.
The data from the different sensor arrays is read-out by a custom made electronic board, digitalised close to the sensor and transmitted wirelessly to a computer and displayed in real time in our software.
The unit we are showing is a part of a decentralized pressure and temperature monitoring system powered by the battery itself and able to communicate wirelessly the data necessary to prolong the battery lifetime to the battery control sytem.
Benefits of the project
During the charge and discharge cycle, a battery cell cyclically changes its volume, it “breathes”. If it is clamped and fixed in place in rigid packaging, with no change in volume possible, it will instead change its pressure. By measuring pressure and temperature changes, with printed pressure sensors placed around and between the battery cells, the battery control system can gain an insight into the state of charge and state of health of the cells. This can help to prevent overcharging, and to perform cell balancing – which maximises battery capacity and lifetime, by correcting any variations in the state of charge between cells in a battery pack. The printed sensors are thin enough that they can be placed to get data from each individual cell, instead of just for the entire battery pack. In fact, there is an optimal pressure at which the battery has the longest lifetime. By keeping the battery at this pressure, the cycle lifetime (the number of charge/discharge cycles a battery can complete in its life) can be improved by 30 to 40 per cent. Our decentralized and wireless approach allows to easily integrate this monitoring system in the battery fabrication process and in the data management protocols of existing battery control systems.
Target Industry
- battery energy storage systems (BESS)
- Automotive
- Consumer Electronics
- Smart Buildings
- Electric grid providers
Organic & Printed Components
- Conductive path
- Interconnection
- Printed dieelectric / insulator
- Printed piezo elements
- Printed sensor
Classical Components
- Dedicated readout electronics
- Computer