Tech Features

Setting a new standard for battery leak testing

Defective cells can shorten battery life, decrease range, and lead to safety issues. A leaky cell housing, one common failure mode for Li-ion batteries, can allow ambient humidity to come in contact with the electrolyte, triggering an exothermic (heat-releasing) chemical reaction.  Currently, the common practice in the battery manufacturing industry is to test cell packaging… Read more »

Proterra beefs up its battery expertise: Q&A with CTO Dustin Grace

Since its founding in 2004, Proterra has grown to become North America’s largest supplier of electric buses. The company has sold some 950 buses to transit agencies, airports, universities, national parks and private companies in 43 states and provinces. Under its Proterra Powered program, the company provides powertrains to other vehicle makers—school buses for Thomas… Read more »

A closer look at the DC Link

The term DC link has traditionally referred to the junction between two power conversion stages where an energy storage element (almost always a capacitor) acts as a buffer for each.  A classic example is the capacitor placed between the rectifier and the voltage source inverter in a mains-supplied variable frequency drive (see Fig. 1). This… Read more »

The technical challenges of bidirectional chargers

For years, we’ve been hearing about an EV technology that promises to be a game-changers: Vehicle-to-Grid (V2G) bidirectional charging. My recent work with one V2G charger developer, Fermata Energy, has convinced me that V2G has found its proverbial killer app: load peak shaving for commercial/industrial energy customers. This article is going to concentrate on the… Read more »

Li-Cycle recovers usable battery-grade materials from shredded Li-ion batteries

Q&A with CEO Ajay Kochhar It’s usually one of the first objections cited by EV naysayers: batteries can’t or won’t be recycled, and they contain hazardous materials that will end up in landfills. In fact, no such sinister scenario is likely—most of the components of Li-ion batteries are valuable, and it’s quite feasible, technically and economically,… Read more »

Scale up micro-solid-state batteries to large EV cells? It’s not so simple.

Q&A with Ilika Technologies Every other scientist in the battery world seems to be working on commercializing large-scale solid-state batteries for use in EVs. The potential for technical and safety benefits is substantial, so there will be a big pot of gold for those who first make real advancements on the automotive level.  Using solid… Read more »

Specialized motor materials and constructions (Part 2)

The previous article in this two-part series looked at specialized materials that are (or will be) used in motors; the focus this time will be on the innovative methods of construction that make motors more suitable for EV traction applications. Separating the wheat from the chaff is especially important here, because hyperbole (and outright fantasy)… Read more »

How to ensure EV traction motor magnets aren’t pushed beyond their operating limits

Avoiding motor demagnetization: John Wanjiku, Technical Specialist at Mentor Graphics, explains the goals of a detailed traction motor design analysis. Neodymium permanent magnets are used in EV traction motors because of their powerful magnetic fields and relatively strong resistance to demagnetization, but they tend to lose their magnetism when exposed to excessive operating temperatures, opposing… Read more »

Specialized motor materials and constructions (Part 1)

When demand drives innovation, the state of the art can progress quite rapidly, but if the demand is not there yet, the end result is often the proverbial “solution in search of a problem.” One of the most prominent examples of this is the lithium-ion battery, which was developed in the 1970s, but didn’t really… Read more »

Solid-state battery tech: What’s close to commercialization, and what’s still years away?

With a fresh round of funding, Wildcat Discovery Technologies is busy expanding its facilities, building up its battery team and doubling down on promising solid-state research projects. We asked the energy storage experts to help clear up the hype around solid-state batteries. Whenever Charged needs to better understand the complexities of the latest and greatest battery… Read more »