Cigarette Filters Into Supercapacitors?!

Into the electrode portion anyway.

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Pop Sci: Scientists Turn Cigarette Butts Into Electrical Storage

The electrical power of the future just might be waiting in ashtrays across the world. Researchers in South Korea discovered that, with a one-step conversion process, cigarette filters turn into great supercapacitors.

Used cigarette filters are composed largely of cellulose acetate. They are disposable, non-biodegradable, toxic and are a threat to the environment after usage. However, it has been reported that cellulose acetate can be directly utilized in the production of carbon materials containing a meso-/micropore structure by only a carbonization process [14].

In essence, the scientists burned the filters in a nitrogen-rich environment, and this made the filter fibers grow pores, further increasing their surface area. According to their results, published in the journal Nanotechnology, these burnt-in-nitrogen fibers stored more energy than materials previously used in supercapacitors.

Link to paper in Nanotechnology

That's some serious materials science hacking.

I'm not sure how this stacks up in terms of cost to other materials being used in current supercapacitors but they're claiming it stores more energy and clearly the machines to mass produce cheap cigarette filters exist so maybe this is a material we'll see utilized by supercapacitor manufacturers in the near future.

For those who aren't familiar with supercapacitor/ultracapacitors, they've been on the verge of replacing rechargeable batteries for it seems like forever but so far they've only managed to find their way into niche applications such as Mazda's regenerative braking system. One of the biggest reasons for their lack of adoption has been that while supercapacitors charge in a fraction of the time of batteries and have lifetimes of many many more charge cycles, their energy densities are conversely poor with even the recent supercapacitor technologies storing less than half the energy of similarly sized conventional batteries.

..and here's a picture of some Maxwell Technologies supercapacitor products from Wikipedia because they look cool

a reply to: theantediluvian

...So, does that mean I need to smoke less or more ?

a reply to: theantediluvian

I find it a little hard to believe that a cigarette filter would beat a 50nm Barium Titanate thin film semiconductor substrate rolled into the same size. But hey, if it's 99% cheaper and half as efficient then we're good to go I guess!

Cheers - Dave

originally posted by: bobs_uruncle
a reply to: theantediluvian

I find it a little hard to believe that a cigarette filter would beat a 50nm Barium Titanate thin film semiconductor substrate rolled into the same size. But hey, if it's 99% cheaper and half as efficient then we're good to go I guess!

for automotive applications, lighter works too.

originally posted by: mbkennel

originally posted by: bobs_uruncle
a reply to: theantediluvian

I find it a little hard to believe that a cigarette filter would beat a 50nm Barium Titanate thin film semiconductor substrate rolled into the same size. But hey, if it's 99% cheaper and half as efficient then we're good to go I guess!

for automotive applications, lighter works too.

Energy density is scalable and based largely on the effective area for super-capacitors as well as the substrate material's ability to retain charge over time. Of course the +/- electrodes also have to have the ability to charge or release energy at reasonable rates without resistive heating. All these parts have weight based on volume. Whether Barium Titanate or cellulose is used as a substrate, the end weight based on equivalent energy density will be close to the same (probably +/- 5%)

Little experiment to try if you are into H2O2 production (HHO).... Get a pair of copper electrodes, say 12 sq inches at a spacing of about 1/10" inch. Power than up in a solution of weak sodium hydroxide and distilled water and measure your H2 output flow. Then use identical plates that are acid etched to produce 2x to 3x the surface area and measure again. Then use a pair of exactly the same electrodes and sputter them with carbon so that you have 1000x to 5000x times the effective area, measure the flow again. Area determines output.

Cheers - Dave

a reply to: bobs_uruncle

So, Dr Who's Tardis could be the ultimate capacitor?