See safety notes below. This is not a build for the timid. Only build in a well ventilated area.
After several years of various experiments, I came upon a workable battery chemistry that is light, safer than Lead-Acid, and easy to make. My original intention was to create a battery that could be manufactured in low-tech environments with limited supplies, and I think I came very close to that ideal with this battery.
After searching the google patent database, I do not believe this idea to be patented. I decided that I could not ever stand to fight the big companies in court if anyone tried to challenge a patent on the material, and I couldn't defend the patent either - as that requires lots of legal representation and great expense. So, in the interest of having my little battery get in the hands of people who need it most - I decided to open source it. I decided to completely share how I built this little guy, and replicate it here with a fresh cell - proving that the technology works.
Composition: Aluminum/AlCl + Hcl + TiO2 + MgO2 + Graphite + Urea (+ mineral oil)
Voltage: 2.10v OCV, the body of work from 2.05v down to 1.80v very similar to lead acid
My current battery appears to still be conditioning, and seems to hold slightly higher voltages for longer each day. I don't know the eventual lifespan or final voltage of this battery, so this is still an unknown. But the behavior seems to reinforce a 2.1v resting voltage, which might eventually be as high as 2.25v.
NOTE: Danger. Be cautious, and wear protective eye wear and disposable gloves. While the battery is ultimately composed of chemicals that are far less nasty than Lead, they are still dangerous. Hydrochloric Acid can burn you, your children, pets, your clothing, the desk - just about anything around you.
Chlorine/Oxygen Gas Hazard: Charging this battery can cause a release of oxygen, which can cause fires. Over charging this battery can cause the release of Chlorine Gas (Cl2) which is nasty stuff. Only build in a well ventilated space, and do not leave an unattended battery charging.
Environmental Note: Do not dump out your battery outside or in the sink. Dispose of battery solutions at your local Hazardous materials collection times. Again, this battery is far less nasty than many, but there's no reason to pollute your local watershed. Be a good steward.