If you read Hackaday regularly, you’ve probably heard that you can use a LASER to create graphene. There’s been a bit of research on how to make practical graphene supercapacitors using the technique (known as LIG or LASER-induced graphene). Researchers at Rice University have been working on this, and apparently they’ve had significant success inducing graphene capacitors on a Kapton substrate. The team has published a paper in Advanced Materials (which is behind a paywall) about their work.
In particular, Rice claims that they have easily produced supercapacitors with an energy density of 3.2 mW/cubic centimeter (that’s what the University’s website reports; they probably mean mW-hours/cubic centimeter) with capacitances near one millifarad per square centimeter. A key benefit of the construction method is that the capacitors continued to work after researchers bent them 10,000 times. A flexible capacitor is useful in wearable devices that would often flex, or in a device like a cell phone that could bend in your back pocket as you sit.
While it is easy to grow graphene with a LASER (we’ve even seen it done with a DVD burner more than once), the interesting part of the Rice team’s research seems to be their use of electrodeposition of manganese dioxide, ferric oxyhydroxide, or polyaniline to create composite positive and negative electrodes. You can see a short video about the new technique below (and that’s certainly not a DVD burner).
Thanks [lethal popcorn] for the tip.
+1 for Universal Laser Systems – My employer!
I worked a bit with these guys on this project since it was such a special use case. They are really doing some cool stuff and, before anyone mentions otherwise, this thing definitely started as a hack. One of the graduate students noticed a black char on Kapton when using a CO2 laser and was like “What is this stuff?” Turned out it was graphene! Since then they have done quite a bit of refining and are making strides in all sorts of ways.
I see “supercapacitors” and hiro hamada pops into my head… I see “LASER-induced” and I think of laser induced plasma… apparently I have big hero 6 on the brain…
The best advice a professor has given me so far is to always check units with dimensional analysis and see if they work out. Instant check whether someone knows what they’re writing about. Helps a ton on multiple choice tests too.
The fun extension of this is defining things in ridiculous units :-)
How do these compare to lipo batteries? Check my math–this battery:
http://www.hobbyking.com/hobbyking/store/__9942__ZIPPY_Flightmax_2200mAh_3S1P_40C.html
Is 10.5 x 3.5 x 2.6 cm (96 cubic cm), and has a capacity of 2200 mAh @ 11.1V, or 24,000 mWh. That comes to 250 mWh / cubic cm.
If that’s right, then there’s still about two orders of magnitude of improvement to catch up to lipos.
but capacitor… discharge cycle is many many more orders of magnitude faster than LiPo.
https://www.tecategroup.com/ultracapacitors-supercapacitors/ultracapacitor-FAQ_files/image006.jpg
Besides the energy storage density, is why they are not as widely used as the main power source as people like to believe. BTW the temperature range isn’t that great either.
There are a lot more info here: https://www.tecategroup.com/ultracapacitors-supercapacitors/ultracapacitor-FAQ.php
Yes but only 118 mWh per gram still abysmal.
Of course, ‘laser’ is an acronym, but I think it’s become a standard word in our lexicon, so capitalizing it comes across quite humorously as shouting. Not complaining, just commenting. =)
I’m so old I still do SONAR too but it isn’t that I don’t think about it.
SONAR, is that like RADAR?
B^)
How about the British term of ASDIC?
God damn it, I’m never gonna be able to un-see this.
“So then we take our ~*LAAAASEEEEERRRR*~ and apply it to the….”
This guy has several videos on creating successively more powerful graphene-based supercaps.
https://www.youtube.com/watch?v=MfEroyS6Ix0
Yah he sold out to edison labs, I know the chemistry to his latest EESD B type, just tweaking it now before I release open source… 5000 F-g
The worst part about it is this guy acts like he came up with it but it was reported in literature in april.
I’m looking forward to seeing the announcement of your release on Hackaday. Good luck.
He never shows real proof of how much storage is actually present, i.e. he’s just connects his prototype to a LED or motor… I don’t believe the claims.
Oh they are real alright, http://www.sciencedirect.com/science/article/pii/S2215038214000107 read this to find out how.
Sure it’s real, but does his “prototype” actually perform to spec?
Related:
https://pse.kaust.edu.sa/Documents/Featured%20Research%20November%202015/030-Advanced_Functional_Materialsalshareef.pdf
If you trust indiegogo, you can already get your graphene super caps in USB charger form!
https://www.indiegogo.com/projects/zap-go-first-graphene-supercapacitor-charger
The tiny size of that wall outlet tells me that it has similar wattage as similar sized chargers. The amount of energy stored in the cap for 5 minute charge is going to be around the same amount store in the regular battery bank that has been charged for 5 minutes. I am already generous that I assume you can get the energy store in the cap with a boost converter efficiently. (See the discharge graph I posted earlier)
I bought a some what reasonable $15 battery bank. I think I can buy a few to cycle around so that I’ll always have backup power and still come out cheaper.
“Also we had to develop a new type of power supply because to get enough power into the charger in a few minutes wouldn’t work with existing power supplies.”
It’s a long shot but perhaps they really did improve the efficiency enough to do it in a small volume without a huge heatsink.
No just power supplies, can you imagine how you need to change power grid to accommodate high spikes of volt/amper bursts when such devices become common and everyone starts to charge?
Eeek. I hate to even mention the: https://www.kickstarter.com/projects/shawnpwest/30-second-charging-rechargeable-battery/description
If I have the possibility I would love to try to create a multi layer 3D component. Something like a multi electrodes (and multi layer) geometric structure, exactly like multi cells batteries that you see one but inside are may in series. I mean, graphene seems to be special due to his atomic structure and then its effect on electrons, I would love to see if a similar concept could be forced in another kind of device. Well that’s Sci-Fi I guess, does exist this degree of sub atomic engineering?Nano tech?
Anyway, to do what if it’s the same of serial cell connection, one may say… Well, I would not limit to serial connection and I would see if will be generated electromagnetic patterns or some other strange / unusual behavior.
I’ve been doing this on Kapton for the last few months and it works well.
Pelukeitor Site
https://www.youtube.com/c/pelukeitor/videos