Countless breakthroughs have been announced over the last decade, time and again these advances failed to translate into commercial batteries. One difficult thing about developing better batteries is that the technology is still poorly understood. Changing one part of a battery—say, by introducing a new electrode—can produce unforeseen problems, some of which can’t be detected without years of testing.
LeVine describes what went wrong with Envia. In 2006 Envia had licensed a promising material developed by researchers at Argonne National Laboratory. Subsequently, a major problem was discovered. The problem—which one battery company executive called a “doom factor”—was that over time, the voltage at which the battery operated changed in ways that made it unusable. Argonne researchers investigated the problem and found no ready answer. They didn’t understand the basic chemistry and physics of the material well enough to grasp precisely what was going wrong, let alone fix it, LeVine writes.
With its experimental material for the opposite electrode, this one based on silicon, Envia faced another challenge. Researchers had seemingly solved the major problem with silicon electrodes—their tendency to fall apart. But the solution required impractical manufacturing techniques.
When Envia made its announcement in 2012, it seemed to have figured out how to make both these experimental materials work. It developed a version of the silicon electrode that could be manufactured more cheaply. And through trial and error it had stumbled upon a combination of coatings that stabilized the voltage of the Argonne material.
The results Envia had reported for its battery couldn’t be reproduced, understanding the problem became crucial. Even tiny changes to the composition of a material can have a significant impact on performance, so for all Envia knew, its record-setting battery worked because of a contaminant in a batch of material from one of its suppliers.
The story of Envia stands in sharp contrast to what’s turned out to be the most successful recent effort to cut the price of batteries and improve their performance. This success hasn’t come from a breakthrough but from the close partnership between Tesla Motors and the major battery cell supplier Panasonic. Since 2008, the cost of Tesla’s battery packs has been cut approximately in half, while the storage capacity has increased by about 60 percent. Tesla didn’t attempt to radically change the chemistry or materials in lithium-ion batteries; rather, it made incremental engineering and manufacturing improvements.
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