Supercapacitors have found their place in many different applications where high power densities, safety and the ability to charge at low temperatures are more important than high energy density. However, they still lack the energy density in order to be used in applications where energy is needed longer than for 30 to 60 seconds.

Lithium-Ion batteries are a technically poor choice for charge-discharge events under 10 minutes due to self-heating and the attributed effects on lifetime. This is commonly solved by simply oversizing the battery, resulting in more volume and weight being occupied than needed out of a pure energy content perspective. Nevertheless, Lithium-Ion batteries today are the most economical choice today even for charge-discharge events below 5 min, as their overall cost per kWh is low and keeps decreasing with new innovations in both electrochemical and process technology.

The performance of supercapacitors and Lithium-Ion batteries thus leaves a gap for high power pulse applications with charge-discharge events lasting between 15 seconds and 15 minutes. 

Skeleton Technologies has been addressing this performance gap by integrating supercapacitors with Li-ion batteries as well as by developing the SuperBattery technology. Both approaches are useful when trying to address high power charge and discharge events with high efficiency while keeping energy density higher than 60 Wh/kg. While both approaches do not have enough energy density to replace Lithium-Ion technology for BEV traction batteries, they provide attractive solutions for weight-, volume-, and cost-efficient energy storage for 15 seconds to 15 min high power applications. 

We will delve into the potential of the newly developed “SuperBattery” technology, compare it to current supercapacitor and LIB technology and the combinations thereof, in addition to outlining different application scenarios in the electrification of on- and off-road applications. 

 In particular, we will investigate how the power profiles of different applications differ and thus favor either a high average or a high peak power solution. Investigated use cases include mining electrification, board-net peak power smoothing and industrial energy efficiency improvements.