e3Power

Modelling made it possible to predict the electrical behaviour of the batteries and other issues related to heating and cooling.

Turku University of Applied Sciences develops battery technology competence – promising results for the electrification of heavy non-road mobile machinery. Turku UAS has studied the electrification of heavy traffic in a wide-ranging project. For example, positive results regarding the use of lithium-titanate oxide (LTO) battery cells were obtained via practical testing and modelling.

Text | Veera Lundén, Administrative Assistant, Turku UAS Photo | Siiri Welling

Together with LUT University and business partners, Turku UAS studied the battery systems of non-road mobile machinery (NRMM) and its different use profiles. Such machinery can be, for example, a combine, tractor, mining dumper, or forestry machine. The study makes it possible to accurately model and map the types of properties needed for the battery cells used in NRMMs.

The research found that using battery solutions equipped with LTO battery cells is a sensible option in heavy machines. According to Eero Immonen, leader of the Computational Engineering and Analysis research group at Turku UAS, LTO batterO ies are safe to use and they also have good durability in cold and hot conditions.

– The battery in a normal electric passenger car can handle approximately 1,000 charges and discharges, while the corresponding readings in the LTO batteries we tested can be more than 10 times higher. We’ve studied the performance and limit values of the cells, which means the properties of different batteries in relation to their intended use, says Immonen.

Usage profiles can be accurately determined

According to Immonen, the project utilised modelling, simulation and practical testing. Modelling and design methods made it possible to examine and demonstrate the performance and limit values of different batteries and NRMMs in a very accurate way.

– The needs for NRMM batteries are often very different from, for example, those used in passenger cars. At the worksite, vehicles are usually exposed to temporary power needs, load variations and changing conditions that affect, among other things, the battery charge and life cycle.

Modelling made it possible to predict the electrical behaviour of the batteries and other issues related to heating and cooling. According to Immonen, battery cells should be used at room temperature for reasons of safety and durability. That’s why either cooling or heating is often required.

One of the test environments was the electric eRallyCross car built at Turku UAS.

– The situations in which a rally cross car is used are comparable to those of an NRMM, because in rally cross the powertrain must also reach isolated operating peaks for short periods of time. This is why the car was also very useful in terms of modelling and ensuring the results in practice.

Aiming to train students and personnel

Immonen stresses the importance of optimisation and modelling when designing battery technology for NRMMs. This is because the production volumes for these machines are considerably lower than for passenger car batteries. The intended uses of NRMMs can be determined very accurately by modelling, which makes it possible to design a battery and electric powertrain for that specific purpose.

The transition to electrification requires increased competence related to the field. Immonen is pleased that the e3Power project has enhanced the personnel’s knowledge and competence. The aim is to include content related to battery technology in ICT, chemical engineering and mechanical engineering studies in order to develop competence in many fields.

– We certainly need experts, and in the future it might be beneficial to add studies related to battery technology, for example, to different programmes as a minor subject. Battery technology could be included in future electrical and automation technology education, says Immonen.

There is a lot of discussion about whether heavy machinery should be electrified to a greater extent and faster. Immonen encourages companies and organisations to invest in clean energy production and partial electrification of heavy machinery rather than full electrification.

– I think that a hybrid model could work for electrification. Not all NRMMs need to be electrified, and it might be enough if some of them are. I also recommend favouring environmentally friendly fuels, such as utilising synthetically produced methane. The combustion engine is very functional, well-known and highly optimised as a technology, and operating it with an environmentally friendly fuel would be sufficient for the climate, explains Immonen.

The research continues

The project succeeded in developing an understanding of the different operating environments batteries are exposed to and mapping the challenges and needs of business partners in terms of manufacturing and using batteries. Valmet Automotive was one of the business partners involved in the project.

Immonen reveals that a continuation of the project is also planned.

– We want to continue the research work in a potential follow-up project. The goal of the follow-up project is to utilise the battery models and measurement data from the e3Power project to optimise battery use over their entire life cycle. At the moment, there is already considerably more data available in comparison to when the e3Power project started in 2019.

According to Immonen, hybrid methods will also be examined in more detail in the follow-up project.