Fudan University team develops superfast charging Li-ion battery cathode
07 April 2013
Researchers at Fudan University with colleagues at the Shanghai Academy of Spaceflight have developed a LiMn2O4 material for a Li-ion battery cathode that exhibits superfast charging capabilities. Their paper is published in the ACS journal Nano Letters.
It is known that from the nature there are a lot of materials rich in facets. Each different facet has different numbers of atoms and effects. According to these natural findings, recently nanomaterials with tailored crystal orientation or facet for electrode materials of solar cells and lithium ion batteries were reported by controlling the preparation conditions such as additives and surroundings, and their performance has greatly improved.
According to the above findings, in this Letter we designed a LiMn2O4 nanotube with exposed (400) planes by using carbon nanotubes (CNTs) as a sacrificed template. It shows that the second-level charge performance and even the amount of conductive agent is in the range for normal practical application. Its charge capacity can be 59.3 mAh/g (54% of the capacity) at the charge rate of 600C (6 s) as a cathode material for aqueous rechargeable lithium batteries (ARLBs) in 0.5 M Li2SO4 aqueous solution.
—Tang et al.
The material also presents excellent cycling behavior due to the porous tube structure to buffer the strain and stress.
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| Credit: ACS, Tang et al. Click to enlarge. |
Resources
Wei Tang, Yuyang Hou, Faxing Wang, Lili Liu, Yuping Wu, and Kai Zhu (2013) LiMn2O4 Nanotube as Cathode Material of Second-Level Charge Capability for Aqueous Rechargeable Batteries. Nano Letters doi: 10.1021/nl400199r
Remarkable performance even at 120C & 97+ mAh/g.
This is what would be required for ultra quick charge 100 to 150 kWh batteries for future EVs with 500+ miles (800+ Km) between charges.
High performance ultra quick chargers (wired and/or wireless) with soon be developed to charge those batteries in 10 to 12 minutes.
During ultra quick charge, very large capacity future battery packs may be temporary split into 3 packs. That would reduce the size of cables required and allow high voltage 3-phase chargers.
Posted by: HarveyD | 07 April 2013 at 07:59 AM
There's yet another chemistry ideal for hybrid cars, assuming the freezing point of the electrolyte is low enough (or can be lowered through additional solutes). Perhaps also for power tools.
Posted by: Engineer-Poet | 07 April 2013 at 08:17 AM
Let's hope that this is just one of many more to follow?
Posted by: HarveyD | 07 April 2013 at 10:10 AM
Let's hope we can get ONE into products.
Posted by: Engineer-Poet | 07 April 2013 at 10:49 AM
IMO what you need is the ability to drive at 75mph for 4 hours and then recharge in 30-40 minutes.
Lets say you need 25 Kw to drive at 75mph, thus you need 100 KwH to drive for 4 hours non stop. If you want to charge this in 30 minutes, you need a 200Kw charger, so lets say we charge in 40 minutes, you need 150KwH, which is possible.
(You probably want a 120 Kwh battery to do this.)
40 minutes if enough for a quick meal and a "freshen up", so this would more or less banish range anxiety (IMO).
With this, you could travel 600 miles in a day with 2 full charges.
The only problem would be the "destination" charge - you might have to charge up near (but not in) your destination, involving an extra journey (unless you had "valet charging" that is).
Posted by: mahonj | 07 April 2013 at 10:57 AM
Most people don't want to drive for 4 hours straight, and the people willing to pay for such a huge battery pack number about as many as Tesla's customers.
What most people want is to get around cheaply. Having a battery which can charge and discharge at 600 C is just what the hybrid makers called for (200 Wh of battery yielding 120 kW means superb regenerative braking). Anything extra allows some PHEV capability, which is lagniappe. Once the engine is downsized and tuned for maximum thermal efficiency, the big gains are realized. THEN the slow march towards bigger and bigger batteries can proceed.
Posted by: Engineer-Poet | 07 April 2013 at 11:47 AM
ahhh EP, well if you want to be sensible, you would build a PHEV, possibly a small (< 5 KwH battery), or medium (<10), and just optimise the ICE - oops, sounds like the Prius PHEV (but with this battery), and what you were saying.
Being sensible and getting rid of "range anxiety" are two different things.
Posted by: mahonj | 07 April 2013 at 01:50 PM
The big gains come from regen braking and elimination of idling in city traffic, boosting city MPG over highway. Improving the thermal efficiency of the powerplant by downsizing it and allowing peak power to be reduced without loss of performance helps on the highway as well, but after the drivetrain the big score there is aerodynamics.
If we made 2000 MWH of batteries per year and had a choice between 10 million vehicles per year with high-efficiency regenerative braking and stop-start using 200 Wh each, or 400,000 PHEVs with 5 kWh each, I'd take the former for national security purposes. If everything suddenly had its fuel consumption drop by 25%, that would be a huge gain.
Posted by: Engineer-Poet | 07 April 2013 at 02:32 PM
Is the vertical axis truly volts or some normalized units?
A high power cell chemistry would allow less total electrode area for the same battery power. I guess the net results would be less cells? How much of an advantage is this for current hybrids?
Posted by: DavidJ | 07 April 2013 at 04:00 PM
Put it for sale and we can watch 600C charging.
Posted by: pat | 07 April 2013 at 08:45 PM
Road side Motels/Hotels will quickly be equipped with appropriate over night charging facilities. Maximum e-energy consumption can easily be regulated for each vehicles and for the whole lot.
Rest stops, eating places, shopping centers, work places etc will also be equipped with appropriate quick & medium charge rate facilities.
Future 125 kWh batteries (an ideal minimum size for mid-size BEVs) will be much smaller and lighter than today's 60 kWh units.
The majority (75+%) will charge their BEVs home with regular level-II, 240 VAC wired/wireless chargers.
Posted by: HarveyD | 08 April 2013 at 01:21 PM
Road side Motels/Hotels will quickly be equipped with appropriate over night charging facilities. Maximum e-energy consumption can easily be regulated for each vehicles and for the whole lot.
Rest stops, eating places, shopping centers, work places etc will also be equipped with appropriate quick & medium charge rate facilities.
Future 125 kWh batteries (an ideal minimum size for mid-size BEVs) will be much smaller and lighter than today's 60 kWh units.
The majority (75+%) will charge their BEVs home with regular level-II, 240 VAC wired/wireless chargers.
Posted by: HarveyD | 08 April 2013 at 01:22 PM
Test
Posted by: HarveyD | 08 April 2013 at 04:20 PM
I'm with EP on this: Who wants to drive 4 straight hours?!? Ok, I admit that I'm a bit ADHD and being confined in a car for more than 2.5-3 hours without a chance to stop and walk around, eat, etc...NO! It makes me even more antsy than I am normally!
You couldn't pay me to drive like that so I'll take a nice 60-70kWh and rapid recharge any day. I'm not paying extra for batteries I won't use.
Posted by: DaveD | 09 April 2013 at 09:22 AM
On long trips, my wife and I drive 800 Km/day. We change driver every 200 Km or about every 2 hours. We make a 45 minutes stop after 4 hours or 400 Km.
The minimum range for our future e-car would be 400 Km + a 100 Km safety margin = 500 Km.
Since affordable e-cars with 500+ Km range may not be available before 2020 or so, we will drive HEVs for another 7+ years?
Posted by: HarveyD | 09 April 2013 at 04:15 PM
I foresee something like a Tesla-engineered VW Golf (downsized Model X?) with a hitch and jack for a generator trailer. Some generator trailers may have auxiliary cargo bays. It would be the best of both worlds.
Posted by: Engineer-Poet | 09 April 2013 at 04:49 PM
A range extender generator trailer may be a logical 'short term' solution for the next 5 to 7 years or so or until such times as 600 to 1200 Wh/Kg quick charge, long lasting, affordable batteries become common place.
Future 125 to 150 kWh ultra quick charge battery packs will weight and cost a lot less than current 60 kWh units used by Tesla and much less than the 85 kWh units used in the Model S-85.
Batteries and chargers evolution will solve the e-range problems. Much lighter future e-vehicles with reduced wind and rolling resistance will also help.
BEVs with ICEVs equivalent range (about 800 Km) will become common place early in the next decade. It is just a question of time.
Transparent 50+% efficient roof-boot-hood-window mounted solar panels could become another way to extend range and get free recharges while working-eating-shopping and/or driving.
Posted by: HarveyD | 10 April 2013 at 02:08 PM
It's a given that the 50 kWh affordable battery will arrive a long time before the 600 kWh affordable battery. While I have no objection to the latter, waiting the extra 10-20 years is not something we can do; generator trailers and electrified roads are both viable solutions to the range problem, and deserve to be pursued on their own merits.
Posted by: Engineer-Poet | 11 April 2013 at 02:56 AM