A Microhybrid is Not a Tiny Car
This week’s issue has C&EN’s update on what’s going on with the Obama-touted advanced battery industry. In short, the U.S. can make many, many big batteries for various flavors of electric vehicles. More batteries, in fact, that the U.S. has electric vehicles.
One flavor of vehicle that may be a new one to many is a microhybrid. These are not tiny cars, nor are they like the all-electric Nissan Leaf or plug-in hybrid Chevy Volt. Rather, a microhybrid system is part of a less radical design intended to help gas-powered cars use less gas. They use some version of what are called start-stop batteries. Andy Chu, vice president of marketing & communications at battery firm A123 Systems explains:
“With start stop batteries, also called micro hybrid batteries, the primary function of the system is that it turns the engine off when you stop. And it turns the engine back on automatically. Just by turning off the engine at a stoplight you can save a few percent on fuel economy. Some of the batteries just crank the engine. But when you ask it to do other things – like launch assist – or move the vehicle from a stopping point - that is the hybrid function. This is great because the battery can respond instantaneously.
You need something beyond typical lead acid, like for regenerative braking. The A123 solution has higher charge capability, then you don’t waste braking energy as heat. Also, it extends the life span – you use the battery much harder – with A123 you don’t need to replace the battery as often as with a lead acid. Weight is another advantage that helps with fuel economy savings. Compared to a lead acid version, we expect 50% better fuel economy gain. If you gain 10% with lead acid, you’d gain 15% with our battery. It is very difficult to save weight in vehicles. A lead battery is very heavy – so its easy to take weight out there.
Automakers, especially in Europe, are really moving to microhybrids. They require very little design change; the battery and alternator are a little bigger, lighter, and provide better fuel economy. They are easy to integrate. So microhybrids are part of our message – though electric vehicles are the sexy topic, advanced batteries can be used across a wide variety of vehicles.”
Lux Research analyst Kevin See says the hybrid-you’ve-never-heard-of will be responsible for the bulk of future growth of energy storage technologies for vehicles, along with batteries for electric bikes. “Although battery prices for all-electric and hybrid passenger cars are dropping, they’re not dropping far enough or quickly enough to fuel the sort of broad adoption that advocates expect,” says See. “Instead, the substantial growth we see for vehicle-related storage technologies will be powered mostly by e-bikes – which are shifting from lead acid to Li-ion battery technology – and microhybrids, which offer a more incremental, low-risk way for automakers to improve fuel efficiencies.”
A Lux Research report states that microhybrids “ are set to surpass these other passenger vehicle types in terms of both total storage and dollars in 2016, growing from 5.1 GWh and $495 million, to 41 GWh and $3.1 billion – CAGRs of 52% and 44%, respectively.”