I've built some small 5cmx5cm supercapacitor batteries to test my own conductive ink. Two are showing a negative volt reading. I've been careful with a steady 1.2v charge and correct polarity contacts. Can anyone advise?

 

Can anyone advise?

Not without more information.
Presumably your DIY ink is being used for one (or more?) electrode. Is it possible the gemisch in your supercapacitor is acting like a battery? It is not uncommon to get the poles of a battery confused.

 

Yes, same ink on both cathode and anode with liquid Sodium Sulphate electrolyte on a fabric separator.

 

If it's symmetrical, how do you know what are the "correct" contacts?

Say your contacts are labeled A and C. You connect the positive lead of the charger to A and the negative lead to C. After charging, what is the voltage of A relative to C?

Then, what happens if you reverse the charger connections with a new cell and repeat?

 

I've attached electrodes - and + correctly to the charger and matched leads to the multimeter. Reversing the meter leads corrects the polarity but why?

 

If it's a non-polar capacitor, you should be able to charge it one direction and verify with the meter, then reverse the charger and charge it in the other direction and verify again. My guess is you're seeing something electrochemical, not capacitive.

 

If it's a non-polar capacitor, you should be able to charge it one direction and verify with the meter, then reverse the charger and charge it in the other direction and verify again. My guess is you're seeing something electrochemical, not capacitive.

OK. Thanks for your replies guys,have a good Christmas.