I want to learn about engineering and know very little. I want to learn more about the creation of batteries or uses for them (not the creation of batteries using acid, preferably something safe such has salt water batteries). BTW I do not want to choose a project myself just do one offered since I have a bad choice in projects since I can be over ambitious and I’m known to not be as careful as I should.


Look up the science behind it, then go all Cave Johnson on it to make an LED light up using it.

Under the assumption your lemon battery produces 1mA at 0.7V, how many lemon batteries are needed to equal the power output of one of the commonly-used FRC batteries?


Research at least 5 different types of battery chemistry (including the type which is legal on FRC robots). List out pros and cons for each type. Answer the questions: Is the battery type used in FRC the ideal solution? Why or why not?

Not technically a battery… technically a capacitor… but now we’re having that debate again.

The lemon battery above is a good one and you can do similar things with other fruit and vegetables. You, as a human being, are also a battery BUT a terrible one (though The Matrix would have you believe otherwise).

alright thanks, BTW I’m buying nichrome wire on Saturday for a project, and I am gonna have quite a bit extra any idea as to what I could use excess wire for.

That’s fun stuff! You can use it to make a custom toaster or a hot wire foam cutter. You can also use it to make a heating element for heating polycarbonate for bending.

There are also real salt water batteries. The navy used to use them to power sonobuoys - the buoy had both the anode and cathode plates, and the sea provided the saltwater electrolyte. Unfortunately, they were rather expensive, using some sort of silver salt IIRC.

These are still in use as well.

I made burrito batteries for our chem-e-car team. They did well, placing 7th in the national competition. The basic instructions are the same. Instead of putting an alligator clip in the activated carbon we soldered wires onto copper strips and placed the strips in between 2 layers of carbon. Putting some pressure cell was helpful (we thought to keep good electrical contact between the carbon). We put the cell between two pieces of polycarb and used two hand clamps to apply some pressure.

The last thing we did gave us more power but probably could have led to the car being disqualified. We added NaOH to the electrolyte (0.5-1 M in the solution – which is quite a lot). I think now that we were just oxidizing some of the aluminum and heating the cell up (exothermic) and that in turn sped up the battery redox reaction. At nationals, I think we had to make the batteries earlier, so the reaction went on longer, and during one run the batteries were “smoking” (steaming) at the end of the run. I’m glad the judges didn’t see that.