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Powering Phones, PCs Using Sugar
Nerval's Lobster writes "A team of researchers at Virginia Tech University have developed a battery with energy density an order of magnitude higher than lithium-ion batteries, while being almost endlessly rechargeable and biodegradable as well – because it's made of sugar. The battery is an enzymatic biofuel fuel cell – a type of fuel cell that uses a catalyst to strip molecules from molecules of a fuel material. Instead of using platinum or nickel for catalysts, however, biofuel cells use the catalysts made from enzymes similar to those used to break down and digest food in the body. Sugar is a good fuel material because it is energy dense, easy to obtain and transport, and so simple to biodegrade that almost anything biological can eat it. Sugar-based fuel cells aren't new, but existing designs use only a small number of enzymes that don't oxidize the sugar completely, meaning the resulting battery can hold only small amounts of energy that it releases slowly. A new design that uses 13 enzymes that can circulate freely to get better access to sugar molecules, however, is able to store energy at a density of 596 amp-hours per kilogram – an order of magnitude higher than lithium-ion batteries, according to Y.H. Percival Zhang, who studies biological systems engineering at the College of Agriculture and Life Sciences and College of Engineering at Virginia Tech. "Sugar is a perfect energy storage compound in nature," Zhang said in a statement announcing publication in Nature Communications of his paper describing the battery. "So it's only logical that we try to harness this natural power in an environmentally friendly way to produce a battery.""
Sweet!
Watt hours would be more helpful. Amp hours are meaningless without associated volts.
If this thing takes off, I can imagine in a few years the highly subsidized corn industry trying to sell high concentration fructose batteries, marketing them as "corn sugar fuel cells".
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If the battery is based off enzymatic reactions won't temperature be a massive variable?
The linked abstract indicates around 0.25 mW/cm^2 (electron exchange membrane area). I'm not in any way a fuel cell expert, but that seems kind of low. Other fuel cells get from 0.2 to 2 Watts (not mW) /cm^2.
Sure, sugar has a high energy density, and this project uses it efficiently. But the batteries would be huge, to get reasonable power.
Never going to happen.
Stuff like this has been done before - and it always sounds good - but they're burying the lead.
Enzymes degrade. They're just made of amino acids - they're not long term structures. It's why our bodies cycle and replace them all the time, and its why every single commercial product based on enzymes is single-use only. With time - and we're talking weeks, not years - they fall apart and stop working due to hydrolysis and self-reactions and what not.
This is why there was a lot of excitement when MIT successfully produced completely solid-state glucose fuel cells. Because a solid-state technology is not enzyme based, and would degrade much, much more slowly (also has other neat properties: like you can implant it).
The big news in...well just about anything, would be if they'd built a battery with a biological component that could self-regenerate the enzymes it needed to operate. That would make me excited - since we'd finally be talking about something you could actually build a useful and long-term product out of (also creating some hilarious new failure modes - 'sorry, your battery has developed an infection - please bring it to tech support for antibiotic treatment').
It's not a battery. It's a fuel cell. The reaction is not internally reversible. Once all the accessible sugar has been oxidized, you need new sugar to refuel it. It doesn't recharge. Most likely you wouldn't bother to refuel it at all. You'd treat it as a disposable that you simply replace, like an alkaline cell. The quoted 596 Ah/kg compares very favorably to the 92 Ah/kg of an alkaline. Of course, that's comparing a theoretical charge density calculated from lab equipment to a product. By the time you squeeze the lab equipment into the AA or AAA form factor, you can expect that quoted 596 to suffer rather badly.
...but wake me up when it can use sucrose.
Why do you hate America? It needs to use corn syrup.
"They that can give up essential liberty to obtain a little temporary safety deserve neither liberty nor safety."
How long do the enzymes last? is probably the question at the front of my mind... related to life and charge cycles, sure, but if you don't "feed" it, do they deteriorate?
The bigger problem, I would think, is how practical is it to handle these? Last thing you want is ants getting into your 500Ah battery and blowing the crap out of it. Do they have to be "cleaned"? Do the enzymes have to be replenished (a nice little sideline for the battery company selling you replacement enzymes - until you fill it with cheap Chinese enzymes and then it stops working)? Does it have to be *cleaned*?
See, to me, the prevelance of a battery is highly dependent on its maintenance. Sure, we used to have to maintain lead-acids, but nowadays they are throw-and-replace or sealed anyway. All household batteries are maintenance-free, even the rechargeable. All coin batteries. All large batteries for UPS, car starters, solar systems, alarms, etc.
Hell, even "electric" cars have a maintenance-free battery that you have to swap out because the maintenance is ridiculous.
Honestly, I'd rather have a battery I can "recharge" with sugar that only does 5Ah instead of 500 and doesn't require any other maintenance (i.e. a fuel cell). But, ideally, I'd rather just have a battery that I don't ever have to do anything with but plug it in and then, years later, throw it away.
You can say that we have to be environmental etc. but lead-acid batteries can recycle extremely well. Until this gets close, it's not even worth an article.
And, sorry, but every battery technology that was ever succesful, I had never heard of it until I was holding one in my hand that came with a product (Ni-Cd, NiMH, Li-Ion, etc.). All the thousands of "new" batteries that make the news? I've yet to see a single one hit the stores in even the most limited fashion. As such, I ignore all battery technology until it's available for me to buy, preferably in 12V or AA versions.
I remember reading stories about fuel cells for laptops (powered by alcohol) during the first year of Slashdot. And, supposedly, such cells were going to be sold for popular laptop models in "a few months." Twenty or so years later, I'm still waiting.
If a fuel cell idea is still completely, and totally, lab-bound, it is unlikely to become a product in the next 15-20 years or so, if previous progress on the subject is any guide.
I'm not sure where your thinking process is broken, but I'll give it a try.
Amp-hours isn't a statement of energy. For example, you could have 2 '5 amp-hour' batteries, but because one is 12V and the other 6V, the amount of energy each contains is very different, with the 12V one being able to supply twice as much energy before becoming exhausted. Because this is a new battery technology, we don't know what the voltage of the battery is.
Watts are a statement of power, Joules are a statement of energy, or power over time. Amps are mostly a statement of volume of electron flow. Without knowing the force behind them(voltage), you can't say how much work you can do with them.
I don't read AC A human right
That's still quite a problem when the cell voltage is 0.13 (remember, the cm^2 terms cancel). You'd need to stack 28 cells to get to the nominal LiIon voltage.
Converting the impressive sounding 590 Ah/kg to to the more useful Wh/kg, we get a much less impressive sounding 76 Wh/kg. LiIon is 100-250 Wh/kg depending on exact formulation.