July 2, 2008 – Ultra thin batteries may give a charge to RTLS and other RFID apps, according to Matt Ream, VP of Marketing for Thin Battery Technologies.

You guys create an energy source by printing the battery in a printing process, correct? I think to some people it sounds like science fiction.

REAM: That is correct. We manufacture batteries using a roll to roll printing process Using somewhat standard screen printing processes, we utilize a foundation of flatbed screen printing and rotary screen printing techniques.

Now, I am assuming it is not ink you are printing, so what are you printing on and what materials are you printing with the screen?

REAM: We tend to call them inks, but they are actually a little more like a paste.

Basic materials in a battery are carbon, zinc and manganese dioxide. There is a little bit of laminating in the process as well. Our anode material is actually a laminate of zinc foil, similar in look and feed to heavy aluminum foil.

So you are printing it on the foil.

REAM: Actually there is a base material for the battery cell which is comprised of a PET material.

So you would laminate the strip onto the PET material.

REAM: Right.

And then that would be the laminated pieces of what you are printing on, right?

REAM: Yes, absolutely.

So, then we print the layer of carbon and our cathode material, which is manganese dioxide mixture – kind of a paste, mixed with carbon. Next we insert what they call a piece of separator paper on top of that. We add a couple of drops of electrolyte, put top layer of PET and seal it up.

And now, does it begin actively generating electricity from the moment you make it or is it somehow activated later on, when you need to use it?

REAM: Our batteries are what are referred to as primary battery cells. It is a chemical reaction that creates the voltage in the cell. They are not rechargeable. If you will, the clock starts ticking once you add the electrolyte liquid in the manufacturing process. Primary battery cells are often stored in cold storage to stop the chemical reaction until they are needed.

What kind of applications are you currently using these batteries for?

REAM: We focus on a number of different markets. Specifically in the RFID market, there a variety applications. Battery assisted passive RFID, which is getting a lot of attention now with some of the new chips that are coming onto the market is showing the greatest interest. Obviously, active technologies like RTLS. And finally RF sensor based applications such as time/temperature RFID data loggers.

How do you connect the battery to, let's say an active tag or battery assisted --

REAM: There are a couple of different ways. Think of a thin, flexible, inlay form factor. For these applications, conductive epoxies, similar to the way RFID chips are being attached. There are also conductive tapes that can be used.

Actually, one of our customers uses a mechanical connection that actually crimps them together.

Why would somebody use one of these batteries over another battery? What would make that decision for them?

REAM: There are multiple reasons, but I think the primary driver is form factor. Our batteries are very thin, very flexible. We’ve produced battery form factors thinner than 500 microns. So, for instance, if you want to get a battery into a card form factor, or a smart label, it really is your only choice.

Now is this one pass through the printing press, or are there many passes, a multiple pass printing technique?

REAM: Yes, it is essentially a single pass through the press, but there are multiple operations through the printing process.

Right. You mentioned several things, on your selection process --

REAM: Yes, one of the other reasons that they might choose our technology, it that it is a very green technology. Again, we use carbon, zinc, manganese dioxide, and very recyclable base materials. There are no toxic chemicals like mercury or lithium in there. It is very disposable. Also the ability to integrate with other printed electronic circuits, while sharing substrates has great value in reducing integration and manufacturing costs. Concepts such as printing an RFID antenna directly on the battery have peaked lots of interest.

So, then in that case they would add a chip and presto, it is tagged.

REAM: Absolutely.

Are there other printed whiz-bang applications you guys have that you want to give us a little hint about in the future?

REAM: Yes. You know, specifically in the RFID space, think of a contactless card form factor with a printed display in it for instance. Or more interactive applications like customer loyalty cards and gaming, things of that nature.

A big step we are taking a look at is wireless sensors, things like time-temperature data loggers, which are really gaining a lot of traction food and pharmaceutical distribution.

When you talk to potential customers about using this battery, do they ‘get it’ immediately?

REAM: Absolutely. Since we are selling and partnering with manufacturers and other folks in the technology end of RFID, yes. Once they see the battery, they get it.