Been a while since I purchased Panasonic 3400mah 18650s.
Lots of news recently about graphene and super capicitors among other stuff.
For example, this 1500mah graphene supercapacitor phone charger: Zap&Go first graphene supercapacitor charger | Indiegogo
Any chance we might be seeing better batteries or capacitors soon in normal battery sizes ?
My guess: No, there are no major discontinuities on the horizon in portable energy storage. Rechargeable batteries are already a large scale enterprise, and have been for decades. Improvements seem to have settled in at ~10%/year (not necessarily delivered every year). The demand for a faster rate of improvement is there, so the fact that things aren’t moving faster suggests that the industry is moving as fast as it can.
A new approach, like, say, graphene super-capacitors, will take time to get the kinks out at scale up. In the early days, there will probably be glaring compromises vs the established tech (that IGG project you linked to notes that the things loose about 20% of their stored power in 72 hours — “about the same as LiIon” (um, no)). If they can manage to match the existing tech in most respects and exceed it in another, then they will surely command a premium price. In the end, a transition to a new tech will likely be long.
Also, FWIW, that IGG seems…dubious. They are going to manufacture their own caps, apparently? I think if you wanted an initial product for large capacity supercaps, you could probably find a better target market.
3D lithium ion cells. With way more capacity and low internal resistance. They use copper foam as the base for the cell then layer it up. But it’s a start up and most likely will not have any goodies for us for quite a while.
HKJ has tested some supercaps.
http://lygte-info.dk/review/batteries2012/Cooper%20300F%20supercap%20UK.html
http://lygte-info.dk/review/batteries2012/Maxwell%203000F%20supercap%20UK.html
“Supercaps has a fairly low voltage rating, for higher voltage they must be used in series and this will require a balancing circuit.
This type of supercap can handle extremely high current both charging and discharging.
The discharge and charge curve is linear and the capacitor can be discharge to zero without damage.
The capacitor has a fairly high self discharge.”
“This supercap is roughly the size of a D cell, but the capacity and energy contents is much lower (about 1/10 of an AA cell).”
Some newer LiIon cells also can handle currents past 20A, at higher capacity.
See this thread for some examples Status for 2014