Same type of battery but new location. This one has mg(magnesium) ribbon that I bought from amazon.com. They are about 40ft rolls despite advertising clams of 65-75ft. I have laid down around 90ft of mg ribbon (about $5 worth) and about 60ft of carbon tow (about $3 worth) and its reading 8mA 1.8V. I think using something a bit more substantial like 100mm x 1mm mg sheet and carbon fiber cloth would be more practical for a larger application.