Efficiency instead of premature recycling
The sustainable use of resources is a key success factor in the energy industry. Instead of prematurely sending electric car batteries for costly and resource-intensive recycling, the use of second-life and overstock batteries in stationary energy storage systems offers a more economically and ecologically promising solution.
"Less energy loss also means that the available energy is better utilized. By reducing losses by up to 70%, CO2 is saved with every storage process and you and your business actively participate in the energy transition - and save money at the same time."
Dr. Nam Truong
CEO & Co-Founder
The best alternative
The resource-efficient use of batteries is also of immense strategic importance for Europe from a geopolitical perspective, as it strengthens the circular economy and reduces our dependence on resources.
After use in electric vehicles, when their capacity has dropped to around 70-80 percent, these batteries are no longer ideal for vehicle operation, but are perfectly suited for use in stationary energy storage systems. Instead of sending them to the costly recycling process or storing them unused, they can be integrated directly into applications such as energy storage solutions for households, industry and commerce or for stabilizing power grids.
This not only extends the life span of batteries, but also increases energy efficiency by making optimum use of existing capacities.
Sample Calculation
Let’s assume that a 40 kWh EV battery is reused in a battery storage system instead of being recycled directly:
1. emissions for a new battery: 80 kg CO₂/kWh × 40 kWh = 3,200 kg CO₂
2. emissions for second-life reconditioning: 20% of this = 640 kg CO₂
3rd saving: 3,200 kg – 640 kg = 2,560 kg CO₂
In figures, this means that the continued use of a 40 kWh battery in stationary battery storage can save around 2,560 kg of CO2 – equivalent to the emissions of a flight from Frankfurt to New York and back per person.
Calculation: CO2 savings = CO2 emissions from new production – CO2 emissions from second-life upgrading x capacity used
*New production: CO2 emissions for the production of a new battery (approx. 61-106kg CO2/kWh depending on the source) and CO2 emissions for the reconditioning of a used battery (significantly lower, approx. 15-30% of new production)
Innovative multilevel inverter innovation
Our modular multilevel inverter technology enables efficient and flexible integration of second-life and overstock batteries in stationary storage systems. In contrast to conventional solutions, our technology ensures that batteries with different state-of-health stages can work together optimally - without any time-consuming sorting or adaptation.
The result is high-performance, scalable energy storage systems that increase grid stability, reduce peak loads, optimize self-consumption, reduce costs in the long term and enable a seamless transition between different battery types.
Thanks to intelligent control and a modular architecture, our system adapts flexibly to different requirements and maximizes the use of available battery capacities. This allows us to extend the life cycle of each battery by up to 67 percent.
In addition to second-life batteries, there are also overstock batteries - unused, brand-new batteries that have been left over due to overproduction or unsold stock. These batteries were originally produced for specific applications in electric vehicles but were not used.
Elaborate storage
The overstock batteries have to be stored expensively and at great expense and can often only be stored for up to two years. Storage is so costly because they have to be charged and discharged at appropriate intervals.
Further use in energy storage systems
The high storage effort and costs involved are another criterion for using overstock batteries in stationary energy storage systems as quickly as possible.
Sustainable use of resources
Overstock batteries make a valuable contribution to the sustainable use of resources. They offer a cost-effective way to make good use of surplus capacity and help to reduce the need to produce new batteries, thereby reducing the environmental footprint.
Recycling batteries is currently expensive, resource-intensive and inefficient. Recycling rates are still low and valuable raw materials such as lithium, nickel and cobalt are often lost because many current processes rely on the incineration of batteries.
The use of second-life and overstock batteries in stationary large-scale storage systems represents an economical alternative to the current recycling process. Energy-intensive companies benefit from reduced costs, improved grid stability and responsible use of valuable resources. Apart from the fact that greenhouse gas emissions have already been released during the production of batteries, second life applications ensure that the batteries contribute to the reduction of further CO2 emissions until the end of their life and when fully utilized.
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