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michka:research:microbial_fuel_cells:cardiff6 [2017-09-17 14:35] – michkamichka:research:microbial_fuel_cells:cardiff6 [2025-10-24 08:45] (current) – nik
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 **[[http://www.zprod.org|Paul Granjon]] & [[http://michkamelo.wordpress.com|Michka Mélo]], May 10th-13th, 2017, Cardiff** **[[http://www.zprod.org|Paul Granjon]] & [[http://michkamelo.wordpress.com|Michka Mélo]], May 10th-13th, 2017, Cardiff**
  
-{{>http://www.flickr.com/photos/foam/37278347985/  ?maxwidth=600}}\\+{{>https://www.flickr.com/photos/foam/37278347985/?maxwidth=600}}
  
 ====0. Abstract==== ====0. Abstract====
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 {{>http://www.flickr.com/photos/foam/37278348485/in/album-72157686272755070/  ?maxwidth=400}}\\ {{>http://www.flickr.com/photos/foam/37278348485/in/album-72157686272755070/  ?maxwidth=400}}\\
  
-     * A small bit of red mono-fiber wire is woven around the (+) electrode wire to clearly distinguish it from the (-) electrode wire+   * A small bit of red mono-fiber wire is woven around the (+) electrode wire to clearly distinguish it from the (-) electrode wire
    * both electrode wires are interwoven on the top to avoid the top (+) electrode to sink away from oxygen    * both electrode wires are interwoven on the top to avoid the top (+) electrode to sink away from oxygen
    * small opening is cut on side of the lid with a cutting clamp to let the electrode wires go through towards the circuit    * small opening is cut on side of the lid with a cutting clamp to let the electrode wires go through towards the circuit
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 {{>http://www.flickr.com/photos/foam/37087471716/  ?maxwidth=400}}\\ {{>http://www.flickr.com/photos/foam/37087471716/  ?maxwidth=400}}\\
    
-     * A small bit of red mono-fiber wire is woven around the (+) electrode wire to clearly distinguish it from the (-) electrode wire+   * A small bit of red mono-fiber wire is woven around the (+) electrode wire to clearly distinguish it from the (-) electrode wire
    * both electrode wires are interwoven on the top to avoid the top (+) electrode to sink away from oxygen    * both electrode wires are interwoven on the top to avoid the top (+) electrode to sink away from oxygen
    * a small opening is cut on side of the lid with a cutting clamp to let the electrode wires go through towards the circuit    * a small opening is cut on side of the lid with a cutting clamp to let the electrode wires go through towards the circuit
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 {{>http://www.flickr.com/photos/foam/37087471856/  ?maxwidth=400}}\\ {{>http://www.flickr.com/photos/foam/37087471856/  ?maxwidth=400}}\\
  
-     * A small bit of red mono-fiber wire is woven around the (+) electrode wire to clearly distinguish it from the (-) electrode wire+   * A small bit of red mono-fiber wire is woven around the (+) electrode wire to clearly distinguish it from the (-) electrode wire
    * both electrode wires are interwoven on the top to avoid the top (+) electrode to sink away from oxygen    * both electrode wires are interwoven on the top to avoid the top (+) electrode to sink away from oxygen
    * a small opening is cut on side of the lid with a cutting clamp to let the electrode wires go through towards the circuit    * a small opening is cut on side of the lid with a cutting clamp to let the electrode wires go through towards the circuit
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    * About one hour after the start of the experiment, it was charged at 0.25 V.    * About one hour after the start of the experiment, it was charged at 0.25 V.
    * After letting it overnight, it was only charged at 1.9 V, and we could not see any charging activity with a typical multimeter.    * After letting it overnight, it was only charged at 1.9 V, and we could not see any charging activity with a typical multimeter.
-   * We would have expected a charge reaching 2.5 V, which is the maximum rating of the supercap…+   * We would have expected a charge reaching 2.5 V, which is the maximum rating of the supercap...
  
 //Consequences on the PHS design// //Consequences on the PHS design//
-  + 
-   * … it is actually a limitation of the S882-Z chip, which will only charge up to 1.8 V (according to the datasheet). +   * ...it is actually a limitation of the S882-Z chip, which will only charge up to 1.8 V (according to the datasheet). 
-   * This means that our supercap will only charge up to 1.8 V, which is not sufficient to power the BBC microbit    * or even open the 1381 voltage detector, which opening rising voltage limit is at 2.4 V.+   * This means that our supercap will only charge up to 1.8 V, which is not sufficient to power the BBC microbit     
 +   * or even open the 1381 voltage detector, which opening rising voltage limit is at 2.4 V.
    * This means that we need another boost converter or charge pump using the 1.8 V charged supercap energy to bring it up to 2.4 V to activate the 1381 voltage detector, and then power the BBC microbit enough to open the gate of the 2N3904 feeding itself longer directly from the energy source.    * This means that we need another boost converter or charge pump using the 1.8 V charged supercap energy to bring it up to 2.4 V to activate the 1381 voltage detector, and then power the BBC microbit enough to open the gate of the 2N3904 feeding itself longer directly from the energy source.
    * Some questions include :    * Some questions include :
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      * Could the second boost converter/charge pump replace the need for a post-Beam circuit (1381 voltage detector + transistors), by directly powering the BBC microbit in the appropriate conditions ?      * Could the second boost converter/charge pump replace the need for a post-Beam circuit (1381 voltage detector + transistors), by directly powering the BBC microbit in the appropriate conditions ?
      * Could we put some MFC in series, and use a different charge pump with a higher supply/input voltage, but a higher output voltage to directly power the BBC microbit from the charge pump ?      * Could we put some MFC in series, and use a different charge pump with a higher supply/input voltage, but a higher output voltage to directly power the BBC microbit from the charge pump ?
-     * Circuit design constraints+     * Circuit design constraints :
        * Few and available (not outdated) components, big enough to be soldered with Fablab equipment.        * Few and available (not outdated) components, big enough to be soldered with Fablab equipment.
        * Available (and not outdated) components.        * Available (and not outdated) components.

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