No lithium-ion batteries required.
Last week Mazda revealed initial details of its new spark-less gasoline engine that will supposedly be even more fuel efficient than both hybrids and EVs. We'll have to wait until 2019 for it to reach production, in the next generation Mazda3, but this new internal combustion engine tech sounds very promising. Called SkyActiv-X, this will be the engine series (that's also supercharged) that'll take Mazda into the year 2030. But how, exactly, does this advanced new technology work?
We're not exactly engineers here and Mazda did leave out many details that could have probably better explained things. Fortunately, Engineering Explained is back to answer our questions - in layman's terms.
Here's the general gist of it: SkyActiv-X is all about compression, specifically homogeneous charge compression ignition. This is similar to how diesel engines use compression ignition, only now Mazda has figured out how to seamlessly change from a standard spark ignition whenever required. This is what Mazda calls Spark Controlled Compression Ignition which results in a 20-30 percent increase in overall efficiency over its current SkyActiv gasoline engines. But the real genius of what Mazda has done is that it figured out how to switch from spark to compression ignition. And therein lies the mystery.
Mazda hasn't revealed how this is done, but Engineering Explained has an excellent theory: the spark plug is used to control the compression ignition timing. Mazda has previously said it would be stupid (not its exact words) to throw away a century's worth of gas engine knowledge and proven know-how solely for lithium-ion powered electric motors. HCCI technology is how it's making internal combustion live on for years to come.