3D-Printed Solid-State Batteries

Could the future of rechargeable batteries lie in 3D-printed solid-state technology? With the potential to offer more power, enhanced safety, faster charging, and extended lifespans, this emerging field holds promising prospects. Moreover, solid-state batteries can be molded into any desired shape, pushing the boundaries of conventional battery design. Various private companies and research laboratories are engaged in a race to unlock the secrets of a battery that could one day replace the ubiquitous lithium-ion cells. Among them, one company stands out by aiming to redefine our perception of batteries through 3D printing.

Before delving into this revolutionary approach, let's briefly explain how a battery functions. Traditionally, batteries convert chemical energy into electricity by utilizing a positive end called the cathode (such as a zinc-coated nail) and a negative end called the anode (like a copper penny). The two ends are connected by an electrolyte, which allows for the flow of electrons. In a simplistic demonstration involving potatoes, the anode releases electrons that travel through a wire to the cathode, generating an electric current. While this example is rudimentary, it highlights the fundamental principle of chemical batteries. Lithium-ion batteries, in particular, have emerged as highly successful versions of this technology, but there is still room for improvement.

Startups in the battery industry are focusing on two crucial elements of battery design: the electrolyte and the anode. Most batteries today utilize liquid electrolytes, typically containing lithium ions that facilitate the movement of charges. However, liquid electrolytes can be volatile, especially when damaged or exposed to high temperatures, as demonstrated by incidents involving battery fires. To address safety concerns, researchers are exploring more stable and non-flammable solid materials as potential alternatives. Various companies are experimenting with electrolytes made from ceramics, glasses, and polymers.

Another area of improvement is the anode material. Conventional lithium-ion batteries employ graphite as the anode material, which performs reasonably well. However, lithium metal has emerged as a more powerful candidate with higher energy storage capacity. Despite its potential, lithium metal presents challenges due to the formation of microscopic structures called dendrites, which can cause short circuits. In the context of liquid electrolytes, dendrite formation has been a significant obstacle. Solid-state batteries, on the other hand, offer the potential to overcome this challenge by employing a solid electrolyte that can resist dendrite growth while facilitating the smooth flow of ions.

Recent years have witnessed significant advancements in solid-state battery materials. Startups are now looking to transition their pilot batteries from the laboratory to large-scale manufacturing facilities. Sakuu, a California-based company, is pushing the boundaries even further by developing solid-state batteries with lithium metal anodes using 3D printing technology. By adopting 3D printing, Sakuu aims to maximize the number of battery layers in a given space, thus enhancing overall battery capacity. Their printer platform, called Sakuu Kavian, allows for the creation of batteries directly within the printer, enabling a transformative approach to battery manufacturing.

While Sakuu has successfully 3D printed solid-state battery prototypes in their laboratory, they have not yet fully printed a functional battery using their prototype. Due to proprietary considerations, the details of the printer prototype were not disclosed during filming. Nevertheless, Sakuu's ongoing research involves testing and optimization to achieve the best battery performance using their unique manufacturing process. Sakuu's printer platform has the capability to print metals, ceramics, and polymers layer by layer, resulting in faster production. The precise speed of the printing process is yet to be determined. Sakuu envisions a future where each machine could produce 40 megawatt hours of energy storage annually, equivalent to approximately 500 electric car batteries per year.

One remarkable advantage of 3D printing in this context is its potential for diverse form factors. Unlike the limitations of roll-to-roll manufacturing, 3D printing offers greater flexibility, allowing batteries to be customized to fit various product designs. This flexibility opens up possibilities for batteries to become integral parts of products, such as being embedded in the temple arm of AR/VR glasses or serving as the case of a cell phone. Beyond simply providing enhanced power, 3D-printed batteries can optimize space utilization within products, thus maximizing their overall performance. Sakuu's prototype printer has a footprint of around 10 meters, marking the initial steps toward realizing this transformative vision.

Undoubtedly, embarking on such a radical transformation carries inherent risks. Sakuu claims that their manufacturing process could reduce costs, but the specific price of their printer was not disclosed. Introducing a new manufacturing process to an established industry presents significant challenges. Furthermore, Sakuu is not alone in pursuing this approach, as other companies like Blackstone Resources and Photocentric are also exploring 3D printing in battery production. While these companies continue their research and development, lithium-ion batteries continue to become more affordable and powerful, making it increasingly difficult for newcomers to compete.

Sakuu is currently constructing its first factory and aims to provide sample batteries to clients by 2023. As the demand for advanced batteries continues to rise, the goal extends beyond improving smartphone battery life. It encompasses enhancing the range of electric vehicles and developing large-scale storage solutions for a decarbonized energy grid. To stand a chance against the dominance of lithium-ion technology, emerging battery technologies must strive for perfection, ensuring the highest quality and longevity to power the future of our technology-driven world.