I have recently been working on an experiment intended to optimize the efficiency of a car battery by determining the optimal concentration of (sulfuric) battery. I have calculated it to be 6 molar, which is what most brands use, however my results show something completely different. Pic related.
I have looked around on the internet to see if there are any papers on the effects of electrolyte concentration on the generation of current, but i have failed to find anything.
Any chemistry majors around here that could tell me what the relationship should theoretically be? Should a graph like mine in theory have a peak at 6 and look like a negative parabola?
The only source of error i have identified is there seems to be higher gas-production when closer to 6M, but this should not have this large of an effect should it?
>>8138853
lithium is the way to go tbqh famiglia
>>8138853
my guess is that your experiments are not replicating the conditions used in your calculations, or in real life.
>>8138855
Lithium does not provide high enough currents, voltages, and is also too expensive for industrial use
>>8138856
Nope, but that should not make a difference in the slightest. The reaction should still occur at the same ratios. To give you an idea of what you are suggesting:
>use lawn-mower engine instead of car-engine to find fuel efficiencies of different oils
>find that cooking oil is 99.999% efficient
>>>must be the lawn mower thats the problem
>>8138853
Try plotting activity on the x axis instead of concentration
>>8138868
If you calculated maximum output at a certain ratio and experiment didn't agree, either your calculations or your setup is wrong.
That's literally the only possibilites.
>>8138889
This.
If you missed a small parameter in your calculations, it will snowball into bullshit data.
>>8138884
Activity?
>>8138991
>I have calculated it to be 6 molar, which is what most brands use, however my results show something completely different.
We're assuming that you can analyze your own data correctly. We're talking about your prediction and experimental setup.
>>8138999
Nice trips
The prediction must be correct unless literally all car-battery manufacturers are using faaar too much acid, which is unlikely. Battery acid is 6M
The set-up is simple - the electrolysis of sulfuric acid by two lead electrodes, connected to an ammeter. It is charged at 3 volts at 0.5 A for one minute. As I said, the procedure is sound, so is the data processing and my prediction. All materials are calibrated.
Either the error is due to electrolysis, or there is something fucked about the electrodes
>>8139003
Due to electrolysis of water*
If you're doing backyard chemistry, something is wrong in your experimental design.
It's not like these trillion dollar car companies decided to spend billions on manufacturing a battery a certain way without verifying their calculations experimentally.
>>8139003
you have to use plates, not electrodes
otherwise, there isn't enough lead for the reaction to proceed fully.
i guarantee 100% this is why you're getting weird numbers.
try increasing the surface area of the electrodes and you'll notice a good jump
also, from what i read, most lead-acid batteries are 4.2-5 mol/L
>>8139007
You are probably right. Assuming 0 gas production , 6 is optimal. Most choose less, though, as to counter it, which according to my experiments lead to more stable currents. The degree to which my results are skewed , however , is probably due to the surface area being so small, in tandem with increased gas production leading to an artificial reduction of surface area as well.
