# Increasing voltage of system of aluminum Air batteries

1. Mar 26, 2009

### Pliskin01

Hello all, this is my first post here and I am glad to be a new member of the PhysicsForums community! I have a question which I believe will be a good challenge for the bright minds here:

I am trying to create a system of Al-Air batteries to power a motor which will be hooked up to an rc car chassis and carry a sizable load. Ive constructed the system seen in the following picture:

each circle represents 3 Al-Air battery cells in a stack connected to each other in series. These stacks are then connected to the other 5 stacks in parallel. Using this set-up, I am able to get readings of 1.6A and 3.0V. While this is enough to turn the motor, it is not enough for the motor to pull any reasonable load placed on it.

The motor requirements are 750mA and 7.5V

Since the current requirement is being met, the voltage just needs to be increased to make the motor turn faster/more strongly (is this correct?).

Is there any way to increase the voltage or make a more efficient battery setup? I am already using 18 cells (6 stacks of 3).

Thank you for reading, any help is appreciated!

Last edited: Mar 26, 2009
2. Mar 26, 2009

### Redbelly98

Staff Emeritus
Welcome to PF!

If you make 3 stacks of 6, you should be able to get 6.0V and 0.8A (twice the voltage, half the current). That might be close enough to the 7.5V motor spec.

EDIT:
You do need to be careful when hooking up batteries in parallel like this, since their voltages
will not be identical.

3. Sep 19, 2010

### navalomalala

My name is Navalona, I am Chemist engineer live in Antsirabe Madagascar, I wish to produce electricity by using Aluminium Air battery. i think that we could work together because we have the same problem: I made only one element and it gives me up to 1.5 Volts but the current is very low about 5mA only; If you know how to incrise it please do not hesitate to contact me.
thank you

4. Sep 19, 2010

### Kalagaraz

Looks to me your stacks are wired parallel which will add the currents, but keep voltage the same. If you wire the stacks in series, you create voltages in a series which are additive and the currents the same.

5. Sep 22, 2010

### vk6kro

Potassium Hydroxide will react with Aluminum regardless of any battery action, so this is a very short lived battery. Don't waste your time on it.

The products are Hydrogen and Potassium Aluminate (in ionic form). The reaction will deplete the Aluminium or the KOH depending on which happens first.

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