maydaverave
10 kW
- Joined
- Jan 13, 2009
- Messages
- 542
Won't somebody think of the childrenEBJ said:
Thread for new battery breakthrough PR releases
- Thread starter Doctorbass
- Start date
AussieJester
1 TW
number1cruncher said:
Aerosol cans and big fast felt typed markers obviously
+1 to dogmans comments
KiM
briogio
100 W
I sure hope this idea goes further than the Zinc Air battery concept that I got all excited about a couple of years ago 
briogio
100 W
Taken from "Green Car Congress";
Tin nanopillars layered between graphene sheets as high-performance anode materials for Li-ion batteries
28 July 2011
Cycling performance of graphene/Sn nanopillar nanostructure anodes at a constant current density of 0.05 A g-1. For comparison, the cycling performance of pure graphene and Sn films under the same conditions are also shown. Ji et al. Click to enlarge.
Researchers with the US Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have embedded arrays of tin (Sn) nanopillars between graphene sheets without adding any polymer binder and carbon black for as-formed use as a high-performance anode material for lithium-ion batteries (LIBs). Electrochemical measurements showed very high reversible capacity and excellent cycling performance at a current density as high as 5 A g-1.
Elemental tin (Sn) is attractive for use in anode materials for high performance rechargeable lithium-ion batteries (LIBs) because of its high theoretical specific capacity (992 mA h g-1) and high operating voltage along with the absence of solvent intercalation. However, the team notes in a paper published in RSC journal Energy & Environmental Science:
...the huge volumetric expansion/shrinkage due to the alloying/dealloying reactions of Sn with lithium (Li) causes severe mechanical disintegration (such as cracking and pulverization), breakdown of the electrical conduction pathways in the electrodes, and even the loss of physical and electronic integrities of the active material.
These enormous volume and structural changes lead to severe degradation of the electrodes upon cycling and dramatically shorten the cycle life of the electrode. As a result, practically durable high-rate and high cycle life Sn-based electrodes have not yet been achieved.
—Ji et al.
Schematic illustration of the graphene/Sn-nanopillar nanostructure preparation procedures. Click to enlarge.
To address this, researchers have tried a variety of tin and carbon composites with different structures and forms, seeking to have the carbon matrices buffer and accommodate the mechanical stress induced by volume expansion and shrinkage.
The team, led by Yuegang Zhang, a staff scientist with Berkeley Lab’s Molecular Foundry, in the Inorganic Nanostructures Facility, assembled the graphene/Sn-nanopillar multilayered nanocomposite anodes by employing both self-assembly and conventional film processing approaches. The rationally designed nanoarchitecture offers a number of mechanical and electrical benefits, they concluded:
The unique geometry of the self-assembled Sn nanopillar arrays with large Li-storage capacity can provide the most freedom for dimension changes and alleviate the mechanical stress/strain induced by the volume change during alloying/dealloying reactions.
The nanopillars can also enhance Li-ion insertion by reducing the diffusion/migration barrier and allow easy penetration of the electrolyte between neighboring nanopillars and hence reduce internal resistance, which is particularly helpful for high energy/power applications.
The addition of flexible and conductive graphene layers to the Sn nanopillar arrays can provide extra “cushion†for the structure to accommodate large volume change induced by Li–Sn alloying/dealloying reactions.>
High electrical conductivity of both constituent materials and their distinctive structures in the nanocomposites can palliate the problems of the slow electrochemical kinetics and sluggish transport rate by offering high surface area and short diffusion pathway for more efficient transport of both electrons and Li-ions.
Graphene sheets also have considerable reversible Li-storage capacity because lithium could be stored not only on both sides of graphene, but also on their significant disorder, edges, vacancies, and covalent sites.
As a result, these assembled graphene/Sn-nanopillar multilayered nanostructures may exhibit synergic properties and display superior electrochemical performance with large reversible capacity, excellent rate capability and cyclic performance, when used as anodes for rechargeable LIBs. Furthermore, polymer binders and conductive additives which are commonly used for other electrode materials are not needed in such integrated electrodes, which will improve the overall energy density of the batteries.
—Ji et al.
To create the composite material, a thin film of tin is deposited onto graphene. Next, another sheet of graphene is transferred on top of the tin film. This process is repeated to create a composite material, which is then heated to 300° Celsius (572° Fahrenheit) in a hydrogen and argon environment. During this heat treatment, the tin film transforms into a series of pillars, increasing the height of the tin layer.
The obtained graphene/Sn multilayered nanocomposites, contained about 70 wt% Sn and 30 wt% graphene.
At a current density of 0.05 A g-1, a half-cell using the multilayered graphene/Sn-nanopillar nanocomposite electrode showed an initial discharge capacity of 734 mA h g-1. At the second charge/discharge cycle, the multilayer anode still had a large reversible capacity of about 714 mA h g-1, which indicates a high capacity retention rate of 97.3% from the first cycle, the authors said. After 15th and 30th cycles, the reversible capacities are preserved at about 723 and 679 mA h g-1 (98.4 and 92.5% retention rates from the first cycle), respectively, indicating very slow capacity decay.
Further cycling tests showed that the graphene/Sn-nanopillar nanocomposite electrodes also exhibited excellent cycle life and rate capability at higher current densities.
Portions of this work at the Molecular Foundry were supported by DOE’s Office of Science.
Resources
Liwen Ji, Zhongkui Tan, Tevye Kuykendall, Eun Ji An, Yanbao Fu, Vincent Battaglia, and Yuegang Zhang (2011) Multilayer nanoassembly of Sn-nanopillar arrays sandwiched between graphene layers for high-capacity lithium storage. Energy & Environmental Science doi: 10.1039/c1ee01592c
Tin nanopillars layered between graphene sheets as high-performance anode materials for Li-ion batteries
28 July 2011
Cycling performance of graphene/Sn nanopillar nanostructure anodes at a constant current density of 0.05 A g-1. For comparison, the cycling performance of pure graphene and Sn films under the same conditions are also shown. Ji et al. Click to enlarge.
Researchers with the US Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have embedded arrays of tin (Sn) nanopillars between graphene sheets without adding any polymer binder and carbon black for as-formed use as a high-performance anode material for lithium-ion batteries (LIBs). Electrochemical measurements showed very high reversible capacity and excellent cycling performance at a current density as high as 5 A g-1.
Elemental tin (Sn) is attractive for use in anode materials for high performance rechargeable lithium-ion batteries (LIBs) because of its high theoretical specific capacity (992 mA h g-1) and high operating voltage along with the absence of solvent intercalation. However, the team notes in a paper published in RSC journal Energy & Environmental Science:
...the huge volumetric expansion/shrinkage due to the alloying/dealloying reactions of Sn with lithium (Li) causes severe mechanical disintegration (such as cracking and pulverization), breakdown of the electrical conduction pathways in the electrodes, and even the loss of physical and electronic integrities of the active material.
These enormous volume and structural changes lead to severe degradation of the electrodes upon cycling and dramatically shorten the cycle life of the electrode. As a result, practically durable high-rate and high cycle life Sn-based electrodes have not yet been achieved.
—Ji et al.
Schematic illustration of the graphene/Sn-nanopillar nanostructure preparation procedures. Click to enlarge.
To address this, researchers have tried a variety of tin and carbon composites with different structures and forms, seeking to have the carbon matrices buffer and accommodate the mechanical stress induced by volume expansion and shrinkage.
The team, led by Yuegang Zhang, a staff scientist with Berkeley Lab’s Molecular Foundry, in the Inorganic Nanostructures Facility, assembled the graphene/Sn-nanopillar multilayered nanocomposite anodes by employing both self-assembly and conventional film processing approaches. The rationally designed nanoarchitecture offers a number of mechanical and electrical benefits, they concluded:
The unique geometry of the self-assembled Sn nanopillar arrays with large Li-storage capacity can provide the most freedom for dimension changes and alleviate the mechanical stress/strain induced by the volume change during alloying/dealloying reactions.
The nanopillars can also enhance Li-ion insertion by reducing the diffusion/migration barrier and allow easy penetration of the electrolyte between neighboring nanopillars and hence reduce internal resistance, which is particularly helpful for high energy/power applications.
The addition of flexible and conductive graphene layers to the Sn nanopillar arrays can provide extra “cushion†for the structure to accommodate large volume change induced by Li–Sn alloying/dealloying reactions.>
High electrical conductivity of both constituent materials and their distinctive structures in the nanocomposites can palliate the problems of the slow electrochemical kinetics and sluggish transport rate by offering high surface area and short diffusion pathway for more efficient transport of both electrons and Li-ions.
Graphene sheets also have considerable reversible Li-storage capacity because lithium could be stored not only on both sides of graphene, but also on their significant disorder, edges, vacancies, and covalent sites.
As a result, these assembled graphene/Sn-nanopillar multilayered nanostructures may exhibit synergic properties and display superior electrochemical performance with large reversible capacity, excellent rate capability and cyclic performance, when used as anodes for rechargeable LIBs. Furthermore, polymer binders and conductive additives which are commonly used for other electrode materials are not needed in such integrated electrodes, which will improve the overall energy density of the batteries.
—Ji et al.
To create the composite material, a thin film of tin is deposited onto graphene. Next, another sheet of graphene is transferred on top of the tin film. This process is repeated to create a composite material, which is then heated to 300° Celsius (572° Fahrenheit) in a hydrogen and argon environment. During this heat treatment, the tin film transforms into a series of pillars, increasing the height of the tin layer.
The obtained graphene/Sn multilayered nanocomposites, contained about 70 wt% Sn and 30 wt% graphene.
At a current density of 0.05 A g-1, a half-cell using the multilayered graphene/Sn-nanopillar nanocomposite electrode showed an initial discharge capacity of 734 mA h g-1. At the second charge/discharge cycle, the multilayer anode still had a large reversible capacity of about 714 mA h g-1, which indicates a high capacity retention rate of 97.3% from the first cycle, the authors said. After 15th and 30th cycles, the reversible capacities are preserved at about 723 and 679 mA h g-1 (98.4 and 92.5% retention rates from the first cycle), respectively, indicating very slow capacity decay.
Further cycling tests showed that the graphene/Sn-nanopillar nanocomposite electrodes also exhibited excellent cycle life and rate capability at higher current densities.
Portions of this work at the Molecular Foundry were supported by DOE’s Office of Science.
Resources
Liwen Ji, Zhongkui Tan, Tevye Kuykendall, Eun Ji An, Yanbao Fu, Vincent Battaglia, and Yuegang Zhang (2011) Multilayer nanoassembly of Sn-nanopillar arrays sandwiched between graphene layers for high-capacity lithium storage. Energy & Environmental Science doi: 10.1039/c1ee01592c
maydaverave
10 kW
- Joined
- Jan 13, 2009
- Messages
- 542
or eestor or a million other could be's. Graphene looks like promising stuff, might not be this particular application that changes the world but I think its probable that something graphene related it going to be revolutionary.briogio said:I sure hope this idea goes further than the Zinc Air battery concept that I got all excited about a couple of years ago
MitchJi
10 MW
Hi,
Sounds promising:
http://www.greencarcongress.com/2011/08/jang-20110811.html
Sounds promising:
http://www.greencarcongress.com/2011/08/jang-20110811.html
New approach to high power energy storage devices: graphene surface-enabled Li ion-exchanging cells
A team from Nanotek Instruments and Angstrom Materials reports on a new strategy for the design of high-power and high energy-density devices based on the massive exchange of lithium ions between surfaces (not the bulk) of two nanostructured electrodes. This approach obviates the need for lithium intercalation or deintercalation—the basic process used in Li-ion batteries.
In a paper published in the ACS journal Nano Letters, the team reports that such surface-enabled, lithium ion-exchanging cells—based on unoptimized materials and configuration—are already capable of storing an energy density of 160 Wh/kgcell, which is some 30 times higher than that (5 Wh/kgcell) of conventional symmetric supercapacitors and comparable to that of Li-ion batteries. They are also capable of delivering a power density of 100 kW/kgcell, which is 10 times higher than that (10 kW/kgcell) of supercapacitors and 100 times higher than that (1 kW/kgcell) of Li-ion batteries.
In both electrodes, massive graphene surfaces in direct contact with liquid electrolyte are capable of rapidly and reversibly capturing lithium ions through surface adsorption and/or surface redox reaction....
.........
......the surface-enabled cells are a class of energy storage cells by itself, distinct from both supercapacitors and lithium-ion batteries....
Crash Machine
100 W
Hey guys has anyone seen these? Lithium titanate is supposed to charge in 10 minutes. Tried to search it on the forum and came up with nothing. The company I understand that is producing these is Altairnano. Also Toshiba is making one called SCiB. Shwinn is using them in a new e-bike called the Tailwind($3200). There doesn't seem to be a published price on either of their websites.
I was just wondering. These would make my long distance trips a dream(got hit by a car,had to cancel this tears trip) and generally change the face of electric vehicles forever seems. I will try to send them an e-mail. I would love to know how much they are. Just figured someone woulda already seen 'em on the forum. Thanks
I was just wondering. These would make my long distance trips a dream(got hit by a car,had to cancel this tears trip) and generally change the face of electric vehicles forever seems. I will try to send them an e-mail. I would love to know how much they are. Just figured someone woulda already seen 'em on the forum. Thanks
liveforphysics
100 TW
Some of us all ready use cells capable of 6min charge, or even 4minute charge now (with the new 15C charge nano-tech's).
You quickly find that it doesn't really matter if a cell can be charged, you're almost always limited by what the charger can output.
I have a 18kw continuous charge setup that runs on 440v 3-phase. Even it can't charge my 2.4kw-hr Nano-Tech pack up as fast as the cells are capable of handling.
You quickly find that it doesn't really matter if a cell can be charged, you're almost always limited by what the charger can output.
I have a 18kw continuous charge setup that runs on 440v 3-phase. Even it can't charge my 2.4kw-hr Nano-Tech pack up as fast as the cells are capable of handling.
grindz145
1 MW
Yeah lithium titanate is expensive, and not energy dense. The only potential benefit it cycle life, which is good according to the cell manufacturers, but the on paper-cycle life means so little unless you have a bunch of experimental data to relate it to, so I bet it's on par with what were using now, just exotic and expensive.
kfong
100 kW
Yeah, it seems that the charger is the limitation these days. Especially a portable one for the road. What I like to see someone do is to make a nano pack with voltage high enough so one can just plug into the 120AC using just a big diode and a limiting resistor. if the pack is setup higher than the wall outlet then a partial quick charge would be possible without any overcharge. Has anyone tried doing this? Problem would be finding a controller and motor that can run at such high voltages.
Doctorbass
100 GW
The one i have do 30 000 cycles and are 15C charge rating.. the only cons is that they have 1.8V instead of 3.6V so the energy density is half common lithium cells
http://www.endless-sphere.com/forum...27750&p=415554&hilit=lithium+titanate#p415554
I still not used them but i plan on doing some test at the end of summer or later
Doc
http://www.endless-sphere.com/forum...27750&p=415554&hilit=lithium+titanate#p415554
I still not used them but i plan on doing some test at the end of summer or later
Doc
Wheazel
10 kW
liveforphysics said:
Thats one big one, did you post a pic of the setup somewhere?
On topic I personally never really had an issue with chargetimes, even my 550w charger does ok.
My big problem is the time it takes to balance the pack.
THe other day I ordered my hyperion 1420 charger to balance my 2x2 zippy 8000pack (12s 16Ah) Imbalance was 0,11 volts and it took like 10hours to get to 0,03v.
I turned it off at that and went to sleep.
Is the hyperion terribad when it comes to balancing power?
ptd
100 W
liveforphysics said:
i can picture luke's pit crew already, lol, waiting with some monstrous generator.
Ykick
1 GW
Wheazel said:
"terribad" - I like that, 'might change my ID to that, LOL... Since the OP's pretty much been answered - I'll murk it up a bit and throw this out there for you. I find the same thing although I have iCharger 106B+. Point is RC chargers can only bleed small amount of current during balancing so it's often a very slow affair, particularly with large packs.
My "ah ha" moment was making a simple pin harness that can connect the iCharger to any cell through the balance connector. Using your RC charger, setup a 1S charge and bring the low cells up to the high cell voltages. 'hope I'm making sense - I'll go take a picture and put this in the "helpful tips" thread. It usually only takes a few minutes for a low cell to fill up using this trick and greatly speeds up pack balance maintenance.
liveforphysics
100 TW
ptd said:
You gotta come to a TTXGP. Its like 10-20 teams all with a crew excitedly waiting with a huge Gen and everyone has >10kw chargers. Its pretty cool.
Pure
10 kW
liveforphysics said:
Then after that, you find the limits of what your source voltage can handle is the next line of failure.
liveforphysics
100 TW
Pure said:
Yes. My 18kw charger is only limited by the 440v 3 phase breakers tripping.
auraslip
10 MW
- Joined
- Mar 5, 2010
- Messages
- 3,535
Re: Huge generators -
I'm thinking in the future it might be more practical to just have a giant battery pack of lead or thundersky cells to charge from and a small generator to recharge that. Or even just a second identical battery pack to charge from. I dunnu. Seems impractical to have a giant 10kw generator, and even then that's a 1 hour charge time for a txxgp bike right?
Re: lifecycles
300,000 cycles! Great, now how many years will it last? I use my lifepo4 pack daily, and I don't think I'll ever do 2000 complete cycles(I rarely ever do more than 50% DOD) in ten years. And ten years is the oft thrown number for life span right? So 300,000 cycles is enough for a century of my uses!
I'm thinking in the future it might be more practical to just have a giant battery pack of lead or thundersky cells to charge from and a small generator to recharge that. Or even just a second identical battery pack to charge from. I dunnu. Seems impractical to have a giant 10kw generator, and even then that's a 1 hour charge time for a txxgp bike right?
Re: lifecycles
300,000 cycles! Great, now how many years will it last? I use my lifepo4 pack daily, and I don't think I'll ever do 2000 complete cycles(I rarely ever do more than 50% DOD) in ten years. And ten years is the oft thrown number for life span right? So 300,000 cycles is enough for a century of my uses!
liveforphysics
100 TW
Bringing a giant ThunderSag pack or whatever to the racetrack to charge from would kinda-sorta work, but it seems like you only spend 20mins racing, and 2hrs between races in the pits, so the little charger for the big pack wouldn't have much time to be keeping the big pack topped off, and you generally need 3-4 charges per day of practice sessions and a race, so you're looking at needing maybe 25-40kw-hr's of ThunderSag's on tap to draw from if you've only got a small gen to be keeping them topped off.
Renting a nice quiet 20,000watt gen with it's own built-in trailer to make transporting it super easy only costs $115 per day, or $300 per week. So, say you're doing 6 TTXGP races a year, you're looking at under $1,000 including fuel to have all the power you need on tap at the track. It would take many years to make paying off a giant ThunderSag pack cost-effective. However, I think it would be fantastic to have something like that anyways, so you could keep it topped off with solar or wind or something. Otherwise, they always call it "emissions free racing" or whatever, but the reality is, we just burned our gas for the race before the race rather than during.
Renting a nice quiet 20,000watt gen with it's own built-in trailer to make transporting it super easy only costs $115 per day, or $300 per week. So, say you're doing 6 TTXGP races a year, you're looking at under $1,000 including fuel to have all the power you need on tap at the track. It would take many years to make paying off a giant ThunderSag pack cost-effective. However, I think it would be fantastic to have something like that anyways, so you could keep it topped off with solar or wind or something. Otherwise, they always call it "emissions free racing" or whatever, but the reality is, we just burned our gas for the race before the race rather than during.
Crash Machine
100 W
Right, so the charger is the weak link. I kinda figure it that way. Besides I am riding on at least 10 years of LifePo already. Even with my long distance rides.
But really charge time aside. Wouldn't the life of the battery overall be what someone buying a new battery be looking for? That's what got me to buy my LiFePo.
How long will the Nano-techs last?
Doesn't really matter much. I am layed up from the acccident and the bike is under repair. Should be up and riding this week. Thanks guys for all the info. May still send them an e-mail and see just how much is too much.
But really charge time aside. Wouldn't the life of the battery overall be what someone buying a new battery be looking for? That's what got me to buy my LiFePo.
How long will the Nano-techs last?
Doesn't really matter much. I am layed up from the acccident and the bike is under repair. Should be up and riding this week. Thanks guys for all the info. May still send them an e-mail and see just how much is too much.
auraslip
10 MW
- Joined
- Mar 5, 2010
- Messages
- 3,535
Good points. I don't know much about ev racing. For some reason I imagined the going around the world and racing every weekend. In any case, it's gonna be a trailer full of batteries and a small gen, or trailer sized gen. Which is KISS? I wonder how far in the future until we have 20kwh battery packs that need to be recharged in the pits in like 10 minutes every 50 laps nascar style? Defenitley would need a huge ass gen AND a buffer pack. It certainly would make you appreciate the crew who keep it all running.
or copper rods....
liveforphysics
100 TW
Crash Machine said:
Long enough that the new battery technology will be so much cheaper and better that you won't care about your old nano-tech pack by the time they wear out.
If you invested in a big heavy bulky low energy Lithium Titanate pack now, you would be throwing it out like an old PC long before it would wear out. lol
Crash Machine
100 W
Ya I always get the "first kid on your block" syndrome. Even the LiFePo I got is getting cheaper now. Thanks for the advice as always. And thanks to whoever made the Android app possible. I don't own a computer so this has made it less cumbersome to post. Long Live the Sphere...
SniperGaulois
10 kW
If you want to read some hype, it sounds interesting. is titanium even conductive?
http://www.ecoseed.org/technology-article-list/article/2-technology/11189-new-material-improves-lithium-ion-batteries-%E2%80%93-o-r-n-l
http://www.ecoseed.org/technology-article-list/article/2-technology/11189-new-material-improves-lithium-ion-batteries-%E2%80%93-o-r-n-l