1. Saving weight and space

One of the biggest breakthroughs in adding power and capacity to our battery system came from the further development and optimization of the internal components. Wattsun’s engineering team works on this daily. Marnix explains: “We succeeded in reducing the number of components and designing them to be lighter. This allowed us to save a lot of weight and space in the casing, without compromising safety. In fact, we passed the vibration and shock tests of the UN38.3 safety test with flying colors.”

2. Filling space with extra battery capacity

Within the casing of the Wattsun Stack, we managed to create space for additional battery capacity. The switch to larger battery cells was important here. At Wattsun, we replaced our 18650 cells with new 21700 cells, which can store more energy. This offers several advantages, including more capacity and a lower weight per stored kilowatt-hour. An additional benefit is that fewer cells are needed for more energy. As a result, we need fewer materials to connect the cells. Marnix explains: “The 21700 cells make it possible to use the (freed-up) space inside the casing more efficiently. The higher energy density of these cells allows us to add even more battery capacity without changing the dimensions of the casing.”

3. Efficiency boost and more power

Finally, through further integration and optimization of the electronics, our engineering team was able to save even more space. A major efficiency boost, Marnix explains: “By using components more intelligently and in a hybrid way, and fully integrating functions like solar charging and 230V charging, we not only saved space but also made the layout more efficient. This allowed us to add more functions while increasing the continuous power by no less than 50%.”

The result

With a 41% increase in capacity, the final result is significant. The capacity of the Dock 3000 increases from 1.4 kWh to 1.8 kWh, and the Pack 3000 goes from 1.8 kWh to 2.3 kWh. The complete Stack now delivers 11 kWh instead of 7.8 kWh of battery capacity. Power has increased by 50%, from 2000 to 3000 watts of continuous power and a peak of up to 6000 watts.

In addition to the increase in power and capacity, the engineering team has added several other customer-requested features. For instance, they responded to user feedback requesting the ability to lift the modules with one hand. Want to know more? Discover everything about the new Wattsun Stack.