Ilika plc (LON:IKA) Chief Executive Officer Graeme Purdy caught up with DirectorsTalk for an exclusive interview to discuss the volumetric energy density increase of its mm-scale Stereax solid-state batteries by introducing wafer-thinning technology.
Q1: This morning, you announced that you had successfully used a wafer-thinning process with your mm-scale batteries, could you explain what wafer-thinning is?
A1: So, our Stereax batteries are deposited onto silicon wafers, in fact we have a pre-pilot line in Southampton that processes these wafers, and they come in standard thicknesses because some of the applications that we’re targeting our mm-scale batteries for are particularly space-sensitive i.e. they’re constrained in terms of the amount of space that’s available. We have been perfecting a technique where the wafers have been reduced in thickness so that you reduce the overall volume of the battery.
Q2: Is wafer thinning proprietary to Ilika or is it widely available in the industry?
A2: Yes, it’s actually a fairly standard industry process, I guess the difference here is that it has never been applied to solid state batteries that we have produced. These wafer-thinning steps are usually used for so-called MEMS devices or sensors that are deployed in environments where volume is a premium.
So, this, for us, is a milestone because we’ve demonstrated that this standard industry process which is often used as the back end of wafer and device preparation can be applied to our batteries.
Q3: So, this sounds like quite an aggressive process, do your cells survive the process and still function?
A3: Yes, that was actually our main concern is the environment in which this wafer-thinning takes place because it is typically a mechanic abrasion process whereby the thickness of the wafer is reduced using a lubricated abrasion process. We were worried this would damage the batteries but in fact, we’ve shown that the batteries survive and in fact cycle as well following the process as they do on wafer prior to the process.
Q4: I’ve seen your photo of a cell and it’s about as thick as a postage stamp balanced on a pound coin, why is such a thin profile important?
A4: The principal application for these mm-scale batteries is for miniature medical devices which are effectively implants that are used on patients. As you can imagine that these implants have to be absolutely as small as possible. In some instance, they’re actually put inside blood vessels and so, if you can produce ultra-thin batteries like these ones then actually it makes it easier to deploy the medical devices.
Q5: Finally, is Ilika’s product launch still on track?
A5: Yes, we mentioned in today’s RNS that we will be doing the launch in Q2 and this is actually a process that we are monitoring very closely at the minute, all of the data so far has been positive.
We’re putting our product through its final QC steps, its Quality Control steps, to make sure it’s fully robust ready for the launch and so far, so good and so, you can expect some more news flow about this coming up shortly.