Engineering Analysis - Adams Patent
Background / Non-Obviousness
First off, it is important to briefly outline the key points that have been codified in 35 USC 103, as well as those that have been affirmed time and time again by judicial precedent. The explicit language of 103(a) perhaps is the best way of making an initial attempt at analysis. The section states that the device is unpatentable is “the differences between the prior art and the subject matter of the patent are such that it would be obvious to a person with ordinary skill in the art at the time of invention. This language was a way of codifying the methods in Hotchkiss that outlined that mere material substitutions or combinations can not be patented unless it required unusual skill in the art unless it produces unexpected results. The latter part of the previous sentence is what is primarily at play in this engineering analysis. Also, we can turn to secondary factors such as commercial success, long felt and unmet need, and failures of others to point to non-obviousness.
Analysis for Patent Validity
As stated by the courts many times, a deep dive into the prior art is necessary when analyzing obviousness. In this case, that is the Wood and Hayes Patents. Let us first outline the key technical aspects of the Hayes patent since it was temporally first. The stated goal of the Hayes device is to make a light, high capacity wet battery that uses Chloride-of-Silver as its positive pole. The main improvement of this device over prior devices was that the silver terminal wire was encased in a glass tube so that deposits were not formed, thus destroying the wire. This patent also mentions the use of Zinc as the negative battery terminal. These two terminals were in a wet solution of either sodium chloride or ammonium chloride/distilled water mixture. The Adams device at hand would not be obvious to someone skilled in the field of batteries at the time of the Hayes patent for several reasons. First off, the two poles of the devices are made from entirely different materials (Mg instead of Ag, and CuCl instead of Zn). Now although under Hotchkiss material substitutions weren’t patentable, the Adams substitution creates a device that has different operating characteristics than the Hayes device. Primarily, the Adams device does not give off fumes unlike the Hayes device, and it does not produce any solid Chlorine waste as in Hayes’ case. This unexpected result and added benefit of the Adams device is enough to show that it is non-obvious under 103 even when considering Hayes. Next, let us consider the Wood patent. This patent is for a wet battery whose negative terminal is made of magnesium, the same as in the Adams device. Wood states that, at the time, it was generally accepted that using Mg as an electrode was unsuccessful due to rapid corrosion. To prove this theory, and the theory that normal water can’t be used as the electrolyte in the battery, Wood ran a few tests. His tests showed that the battery that had ammonium chloride and distilled water was used up in four hours, gave off too much odor and gas but a constant voltage of 1.4V. These negative aspects were enough for Wood to throw away the idea of using water and put his support behind using the electrolyte mixture of ammonium chloride, ammonium nitrate, and sodium dichromate. The Adams patent is valid even in light of the Wood patent, primarily as a result of the device’s stability when using a magnesium electrode and plain water as an electrolyte. The fact that Wood’s patent would lead researches away from the Mg/water combination is enough to prove that it was not obvious for Adams to attempt to make this device. In fact, nowhere in Wood’s claims does it ever refer to using or the benefits of water as the electrolyte. Thus, it is my opinion that in the eyes of 103, the Wood patent, and the Hayes patent, our Adams device is patentable.
Analysis for Patent Invalidity
The issue at hand in this case is quite simple. With regards to our Adams device in light of the Wood and Hayes devices, we are essentially dealing with a material substitution example not unlike that of Hotchkiss v. Greenwood. It has been shown that multiple wet batteries, including the Wood and Hayes cells, have used various combinations of materials for anodes, cathodes, and electrolytes including magnesium for the negative electrode, silver chloride for the positive electrodes and various ammonium chloride solutions as the electrolyte. Anyone with a working knowledge of chemical compounds and their characteristics would know that copper chloride is a reasonable substitute for silver chloride, thus making this a reasonably obvious substitution in trying to make a cell with similar characteristics. As for the magnesium, an electrode made of pure magnesium as outlined in the Wood patent. Thus, making a cell whose electrodes are magnesium and copper chloride would be obvious to anyone with a knowledge of the prior art in the field and attempting to construct a new cell. Lastly, we come to the electrolyte question. One of the things that had been plaguing industry is the waste or fume and gas production of the state of the art cells. In fact, this problem is explicitly contained in both the Wood and Hayes patents. The fact that the Adams device happens to not have this problem simply as a result of combining different elements from the prior art and using water as the electrolyte is a coincidence, and a result that is not even outlined in the claims. Thus, it is my opinion that there is nothing unexpected beyond a combination of prior art and a substitution of materials therein contained in the claims of the Adams patent and therefore it is deemed unpatentable.
Resources = Adams patent (US 2322210), Wood patent (US 1696873), Hayes patent (US 282634)