Electronics

New tech allows lithium batteries to charge faster, and hold charge longer

New tech allows lithium batteries to charge faster, and hold charge longer
Scientists have created a new type of lithium-ion battery that is said to hold a charge ten times longer, and recharge in one-tenth the time of existing li-ions
Scientists have created a new type of lithium-ion battery that is said to hold a charge ten times longer, and recharge in one-tenth the time of existing li-ions
View 1 Image
Scientists have created a new type of lithium-ion battery that is said to hold a charge ten times longer, and recharge in one-tenth the time of existing li-ions
1/1
Scientists have created a new type of lithium-ion battery that is said to hold a charge ten times longer, and recharge in one-tenth the time of existing li-ions

For those of us using smart phones, an all-too-familiar problem is that of a dead battery. The computing power, as well as the multi-purpose abilities of modern-day phones is nothing short of amazing. However, until battery life catches up with the functionality, we're still forced to carry multiple devices. For example, what good is 32GB of memory to store music and movies if it leaves me with a dead phone after an hour or two of my favorite tunes? Even though my phone can easily handle the music and movie abilities of my iPod, I still carry the iPod. I still have a GPS in my car, even though my phone is more than capable. New technology from Northwestern University is aiming to change all that. Engineers there have created an electrode for lithium-ion batteries - the rechargeables commonly found in our devices - that allows them to run ten times longer, while only taking only one-tenth of the time to charge.

"We have found a way to extend a new lithium-ion battery's charge life by 10 times," said Harold H. Kung, in a paper published in the journal Advanced Energy Materials. Kung is professor of chemical and biological engineering at the McCormick School of Engineering and Applied Science. "Even after 150 charges, which would be one year or more of operation, the battery is still five times more effective than lithium-ion batteries on the market today."

Close your eyes for a moment and imagine a week - or more - of battery life. If that doesn't bring a smile to your face, the next statement will: imagine your phone running for a week after charging for only 15 minutes.

Currently, lithium-ion batteries charge by a chemical reaction that occurs when lithium ions are sent back and forth between the two ends of the battery; the anode and the cathode. When the battery is fully charged and in use, the ions travel from the anode through the electrolyte and ultimately make their way to the cathode. When all the ions make their way to the cathode, the battery is dead.

When you charge the battery, you are reversing the process and sending the ions from the cathode to the anode.

The electrode combines two chemical engineering processes to eliminate the two major flaws in lithium-ion battery technology; their limited energy capacity and relatively slow recharge rate. The electrode virtually eliminates these problems and promises super batteries for the next generation of devices.

The first problem is limited energy capacity, which is why your current battery can't maintain a charge for long periods of time. The culprit here is called charge density. Charge density is basically how many lithium ions you can pack into one battery between the anode and cathode. The second problem is charge rate. This problem stems from the speed at which the lithium ions can travel from the cathode to the anode. In essence, speed them up and you have a faster charge.

In its current state, the anode - made up of thin layers of graphene sheets - can only accommodate one lithium atom for every six carbon atoms. Scientists have experimented with replacing the carbon with silicon, as silicon can accommodate much more lithium (four lithium atoms for every silicon atom) than the carbon. The problem is, silicon expands and contracts rapidly during the charging process. This causes the battery to lose its recharge capabilities relatively quickly.

Kung's team fixed the energy capacity problem by stabilizing the silicon. This involved sandwiching silicon between the graphene sheets. This maximizes the amount of ions that can travel through the sheets, while maintaining flexibility so that the battery isn't compromised while charging.

The second problem fixed by Kung's team was the recharge rate. This was accomplished by creating microscopic (10 to 20 nanometers) holes in the graphene sheets. This process was named "in-plane defects" and it allowed the ions a shorter, secondary route to the anode. This reduced the charge time to one-tenth of the previous time it took to charge the battery.

Looking past the implications of longer battery life for your personal devices, the electrode could also make batteries for electric cars smaller, and longer-lasting.

The Northwestern University technology is expected to hit the marketplace in the next three to five years.

10 comments
10 comments
Naoki Watanabe
Even though there have recently been many exciting discoveries in the world of batteries, from carbon foam asymmetric capacitor with a charge cycle of 120,000+, sulfur bound to nanofibres for 10x more capacity, and even a more detailed report on silicon use in batteries from Berkely. But for some reason (Northwestern\'s excellent marketing?) this article was picked up by every tech blog out there since it appeared on physorg a week ago. Regardless is it not too generous to say \"new technology\" when it\'s not really, it\'s a new process in a lab that might be in a product in another half-decade if it pans out technically and economically.
Better stuff; - http://www.physorg.com/news/2011-11-carbon-foam-key-ingredient-battery.html - http://www.physorg.com/news/2011-09-revolutionary-polymer-enables-silicon-lithium-ion.html - http://www.physorg.com/news/2011-10-sulfur-hollow-nanofibers-lithium-ion-battery.html
Gadgeteer
I agree with Naoki. Sorry, but I\'ve grown skeptical thanks to too many breathless announcements like this followed by wondering ten years later, \"Whatever happened to...\" I\'ll believe it when it gets to market. For instance, see the first related story below about a \"100-fold boost in performance.\" That was supposed to be ready in 2-3 years. That story is now 2 1/2 years old. Anyone want to bet whether A123 will be selling this miracle battery within the next six months?
Ramon Leigh
This development team has been heard from before - more than a year ago Kung demonstrated startlingly rapid recharging, something that had already been achieved by \"slippery surface\" design from MIT, which A123 Systems has licensed and is developing. Kung seems to have solved the recharge rate problem somewhat differently than the boys at MIT. BUT, that battery design only addressed recharge rate problems - it did not increase the energy capacity. The KUNG team had done that, and not just theoretically, but in a real operating device. Their claim that they may be able to commercialize as quickly as two years puts them ahead of any other team and they have made far more progress than everyone else at this point. The key to a practical super battery is not really recharge rates (Tesla Model S can recharge their 320 mile battery pack in less than 45 minutes, which is fast enough to be completely practical), nor is it energy density (Tesla\'s pack weighs 1000 pounds). It is affordability, which means a low initial cost and a long lifespan. If Kung\'s battery has ten times the capacity, then it should be much cheaper to make, in terms of dollars per kilowatthour of capacity. At 10 times cheaper, that reduces the cost of the Tesla Model S from $77,000 to $41,000. It will then be far more cost effective, both in initial cost and in operating costs than anything comparable using an ICE drive train.
Jim Sadler
Imagine how many businesses would love to suppress development of such batteries. It would put numerous industries into turmoil. It is rather like expecting Detroit to be eager for electric cars to succeed. Development of factories and processes to produce this product will face a lot of very dedicated opposition.
Will Sharp
It loses half of its energy capacity after a year? It doesn\'t matter how good it was to begin with, that needs to be fixed before this can be taken seriously...
warren52nz
If you read what the developer actually said: \"We have found a way to extend a new lithium-ion battery\'s charge life by 10 times,\" That sounds like they\'ve decreased its self-discharge rate or how long the battery will last before it needs to be replaced. It doesn\'t sound like \"ten times the capacity\" to me otherwise he would have said that because that\'s even better. If it IS ten times the capacity, that\'s a radical breakthrough!
peterhunt21
I always think that the science community should look closely at any photos of flying saucers and work backwardly from them in developing ideas for transportation vehicles.In photos taken we know about the basic shape and we know that they are able to travel great distances and to travel as well as accelerate very quickly.Part of each flying saucer has to provide for energy to power the vehicle,part has to deal with driving the vehicle and part has to do with having an environment that any creatures inside can survive in.Some how flying saucers take energy from the environment and convert it into energy for the vehicle.In the process the energy must be stored so it can be distributed to systems that propel the vehicle,heat the vehicle and provide for the vehicle.What kind of batteries would such a vehicle have,what kind of motor?Any one have any idea of how to contact some source of knowledge that is out of our world for answers? It would be so nice to tap into some resourse that would just give us some basic answers.There might be some really simple design for a battery that is being overlooked.
Scott Bailey
What can\'t people that design electronic devices with big 10\" screens design a series of capacitors that can be used to hold a charge and then a battery. Surely something along this idea could be trialed. As the TABLETS get faster and jam pack themselves with ICECREAM SANDWICH Android 4.0, the days of the sub $2000 laptop are surly numbered.
Please anyone ever trialed this method to give an electronic hand held device a greater number of hours before one needs to re-plug it in to a power point to re-charge?
Thanks S Bailey Queensland, AUSTRALIA.
foxcopy
To warren52nz
The power systems they use is extremely advanced, It not just a power system, it a combined power plant And propulsion system, the energy comes from a Gravitational gradient running thru a controlled feed back, And produces extremely dangerous radiation.
If you want to invent something to obtain energy from The environment all you have to is remember this one thing, There are no ËœFields" No magnetic field, No gravitational fields There are Only Gradients
:) Be Free
foxcopy
Correction Not To warren52nz
To peterhunt21
And
There are No \"Fields\" No magnetic field, No gravitational fields.