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saltwater battery for R/C boat in saltwater? Answered

I Based it here:https://www.instructables.com/id/Water-Powered-Calculator/?ALLSTEPS 
My plan is to put an exposed carbon electrode and an Aluminum Foil at the seawater while traveling
to make it as the boat's battery 
my problem is will I get Thousands of Volts that can be deadly or will i get just what I need 
if the result is thousands of volts its the electric solution at some of the provinces here at the Philippines
Thank you!




Best Answer 5 years ago

A saltwater battery doesn't produce much power. In order to make a salt water battery powerful enough to run a small RC boat the battery would end up much larger than the boat and weigh more than the boat could carry.

Here is an example of a saltwater battery capable of providing up to 12V. The anodes in the battery will last about 8 hours with a 12V 5Amp load. After that time you have to replace the electrodes in the battery as well as the water. But you can see how big the thing is to achieve that amount of power. You can also see it weighs 3.5 lbs without any water in it.

These batteries are very inefficient.

crazy lazy manmpilchfamily

Answer 5 years ago

thanks for your answer but my idea is to expose the carbon rod and aluminum to the seawater because it will ride at a beach i mean that the beach will serve the battery
because it has the salt water I thought that I will get Thousands of Volts that can be deadly because I know that to add the voltage of the saltwater battery is to have a larger space and more acidity imagine how large the sea is.thanks

mpilchfamilycrazy lazy man

Answer 5 years ago

The voltage is determined by the surface area of your anode and cathode that is exposed to the saltwater, not the amount of saltwater you have on the anode and cathode. Your not going to get more voltage just because you have a couple of small rods sticking out the bottom of the boat. You will need about 2lbs worth of carbon and aluminum sticking out the boat and within a certain distance of one another to create the power you will need to run the boat. I think it's safe to say your boat can't handle that added weight.

You also gotta consider how you have your materials configured. You will have to figure out how much voltage and current a set size of carbon rod and aluminum can create. Then figure out how many of that setup you will need wired in series to get there voltage needed then how many additional sets you need wired in parallel to give you the current needed.

As an example that instructable you linked too... The solar calc only needs 2V or 3V at 20-40 microamps. So a AA sized saltwater battery is just enough to power the calc until the anode and cathode need to be replaced or the metals have corroded enough that you need to add more salt water.

So using a saltwater battery to run an RC boat is not going to work. Saltwater batteries are just not efficient enough to be feasible for larger (higher power) applications.