美国研制出一种实现锂电池快速充电的新型电极。筒子们明 ...

新型电极实现锂电池2分钟完成快速充电
美国研制出一种实现锂电池快速充电的新型电极，可以在2分钟内完成充电。
在大部分的现代小玩意中，电池都是必要的部件，随着应用于汽车和电网，预计电池充当的角色更为扩展。但电池也有一些局限，它无法象超级电容那样快速充电，而且随着时间的推移，它的容量会衰减。为了克服这些限制，科学家们试验了各种各样的材料，有时候确实也获得了令人注目的成功。周末，一份论文发表了一种可以实现电池快速充电的技术。这种技术使用了与先前不同的方法和技术，能用于锂基和镍基电池。
The previous work was lithium-specific, and focused on one limit to a battery's recharge rate: how quickly the lithium ions could move within the battery material. By providing greater access to the electrodes, the authors allowed more ions to quickly exchange charge, resulting in a battery with a prodigious charging rate. The researchers increased lithium's transport within the battery by changing the structure of the battery's primary material, LiFePO4.
先前的方法主要针对锂电池，专注于克服电池的充电速度：离子能以多快的速度在电池材料中运动。研究者过去都是通过改变锂电池的主要原料——磷酸铁锂（LiFePO4）——的结构来实现锂离子在电池材料中的快速传递的。而作者则通过提高电极的接触面，使其可以与离子进行快速的电荷交换，实现电池的快速充电。
The new work also gets fast charges, but by a rather different route. The authors, from the University of Illinois, don't focus on the speed of the lithium ions in the battery; instead, they attempt to reduce the distance the ions have to travel before reaching an electrode. As they point out, the time involved in lithium diffusion increases with the square of the distance travelled, so cutting that down can have a very dramatic effect. To reduce this distance, they focus on creating a carefully structured cathode.
新的方法采用了完全不同的技术路线，同样获得了快速充电的效果。来自伊利诺斯大学的论文作者们并不关心离子在电池材料中的运动速度，他们致力于减少离子运动到电极上所行走的距离。他们指出，离子的运行时间与距离的平方成正比，所以减少距离可以获得引人注目的效果。为减少这段距离，他们专注于开发一种结构精密的阴极材料。
The process by which they do this is fairly simple, and lends itself to mass production. They started with a collection of spherical polystyrene pellets. By adjusting the size of these pellets (they used 1.8µm and 466nm pellets), they could adjust the spacing of the electrode features. Once the spheres were packed in place, a layer of opal (a form of silica) was formed on top of them, locking the pattern in place with a more robust material. After that, a layer of nickel was electrodeposited on the opal, which was then etched away. The porosity of the nickel layer was then increased using electropolishing.
他们的制作过程其实相当简单，适合进行大规模生产。开始的时候，他们采用聚苯乙烯小球汇聚的球团，通过调整这些小球的大小（他们选用直径在1.8微米到466纳米之间的小球），可以调整电极的空间特性。当小球的排列符合要求之后，将获得一种类似猫眼石（一种硅元素的结构）的结构，用加强材料将这种排列结构固定下来。然后，在猫眼石结构表面用电沉积法镀上一层镍膜，之后把猫眼石蚀刻掉，再经过电解抛光，增加这些镍膜空隙度。
When the process was done, the porosity—a measure of the empty space in the structure—was about 94 percent, just below the theoretical limit of 96 percent. The authors were left with a nickel wire mesh that was mostly empty space.
当整个过程完成后，空隙度达到94%，刚好低于96%的极限水平。这样一来，作者们就获得了一团包含很多空间的镍丝网。
Into these voids went the battery material, either nickel-metal hydride (NiMH) or a lithium-treated manganese dioxide. The arrangement provides three major advantages, according to the authors: an electrolyte pore network that enables rapid ion transport, a short diffusion distance for the ions to meet the electrodes, and an electrode with high electron conductivity. All of these make for a battery that acts a lot like a supercapacitor when it comes to charge/discharge rates.
这些空间将用来填充电池材料，可以是镍金属氢化物，也可以是掺杂锂的二氧化锰。作者称这种布局具备三大优点：电镀网孔有利于离子的快速运动，离子到达电极的距离缩短，电极导电性提高。这些优点的叠加使得做出来的电池在充放电速度上可以与超级电容相媲美。
With the NiMH battery material, the electrodes could deliver 75 percent of the normal capacity of the battery in 2.7 seconds; it only took 20 seconds to recharge it to 90 percent of its capacity, and these values were stable for 100 charge/discharge cycles. The lithium material didn't work quite as well, but was still impressive. At high rates of discharge, it could handle 75 percent of its normal capacity, and still stored a third of its regular capacity when discharged at over a thousand times the normal rate.
对于镍氢电池，这种电池可以在2.7秒的时间内放出标准电量的75%，而充满90%的电量只需要20秒。按这样的强度经过100次充放循环，电池性能还可以保持稳定。锂电池表现稍微差一点，但也相当了不起。标准电量的75%可以实现高速放电，而经过1000次循环后，还能保持三分之一的存储能力。
A full-scale lithium battery made with the electrode could be charged to 75 percent within a minute, and hit 90 percent within two minutes.
完全用这种电极制作的锂电池，能做到1分钟充满75%的电量，充满90%的电量只需要2分钟。
There are a few nice features of this work. As the authors noted, the electrodes are created using techniques that can scale to mass production, and the electrodes themselves could work with a variety of battery materials, such as the lithium and nickel used here. It may also be possible to merge them with the LiFePO4 used in the earlier work. A fully integrated system, with materials designed to work specifically with these electrodes, could increase their performance even further.
作者称这种技术还有其他一些优异的特性，可以实现大规模生产，除了应用于上文提到的锂材料和镍材料，它可以应用于更多的电池材料。先前的磷酸铁锂材料也能结合采用这种技术。通过专门设计，使电池材料与这种电极匹配，可以进一步提升电池性能。
Of course, that ultimately pushes us up against the issue of supplying sufficient current in the short time frames needed to charge the battery this fast. It might work great for a small battery, like a cell phone, but could create challenges if we're looking to create a fast-charge electric car.
当然，使用这么高的速度给电池充电，我们最终不可避免将面临提供大电流的问题。对于类似手机上使用的小电池来说，这样快速充电表现优异，但是如果想用于对电动汽车快速充电，那将是一项挑战。
http://article.yeeyan.org/view/211199/182436
http://arstechnica.com/science/n ... -in-two-minutes.ars新型电极实现锂电池2分钟完成快速充电
美国研制出一种实现锂电池快速充电的新型电极，可以在2分钟内完成充电。
在大部分的现代小玩意中，电池都是必要的部件，随着应用于汽车和电网，预计电池充当的角色更为扩展。但电池也有一些局限，它无法象超级电容那样快速充电，而且随着时间的推移，它的容量会衰减。为了克服这些限制，科学家们试验了各种各样的材料，有时候确实也获得了令人注目的成功。周末，一份论文发表了一种可以实现电池快速充电的技术。这种技术使用了与先前不同的方法和技术，能用于锂基和镍基电池。
The previous work was lithium-specific, and focused on one limit to a battery's recharge rate: how quickly the lithium ions could move within the battery material. By providing greater access to the electrodes, the authors allowed more ions to quickly exchange charge, resulting in a battery with a prodigious charging rate. The researchers increased lithium's transport within the battery by changing the structure of the battery's primary material, LiFePO4.
先前的方法主要针对锂电池，专注于克服电池的充电速度：离子能以多快的速度在电池材料中运动。研究者过去都是通过改变锂电池的主要原料——磷酸铁锂（LiFePO4）——的结构来实现锂离子在电池材料中的快速传递的。而作者则通过提高电极的接触面，使其可以与离子进行快速的电荷交换，实现电池的快速充电。
The new work also gets fast charges, but by a rather different route. The authors, from the University of Illinois, don't focus on the speed of the lithium ions in the battery; instead, they attempt to reduce the distance the ions have to travel before reaching an electrode. As they point out, the time involved in lithium diffusion increases with the square of the distance travelled, so cutting that down can have a very dramatic effect. To reduce this distance, they focus on creating a carefully structured cathode.
新的方法采用了完全不同的技术路线，同样获得了快速充电的效果。来自伊利诺斯大学的论文作者们并不关心离子在电池材料中的运动速度，他们致力于减少离子运动到电极上所行走的距离。他们指出，离子的运行时间与距离的平方成正比，所以减少距离可以获得引人注目的效果。为减少这段距离，他们专注于开发一种结构精密的阴极材料。
The process by which they do this is fairly simple, and lends itself to mass production. They started with a collection of spherical polystyrene pellets. By adjusting the size of these pellets (they used 1.8µm and 466nm pellets), they could adjust the spacing of the electrode features. Once the spheres were packed in place, a layer of opal (a form of silica) was formed on top of them, locking the pattern in place with a more robust material. After that, a layer of nickel was electrodeposited on the opal, which was then etched away. The porosity of the nickel layer was then increased using electropolishing.
他们的制作过程其实相当简单，适合进行大规模生产。开始的时候，他们采用聚苯乙烯小球汇聚的球团，通过调整这些小球的大小（他们选用直径在1.8微米到466纳米之间的小球），可以调整电极的空间特性。当小球的排列符合要求之后，将获得一种类似猫眼石（一种硅元素的结构）的结构，用加强材料将这种排列结构固定下来。然后，在猫眼石结构表面用电沉积法镀上一层镍膜，之后把猫眼石蚀刻掉，再经过电解抛光，增加这些镍膜空隙度。
When the process was done, the porosity—a measure of the empty space in the structure—was about 94 percent, just below the theoretical limit of 96 percent. The authors were left with a nickel wire mesh that was mostly empty space.
当整个过程完成后，空隙度达到94%，刚好低于96%的极限水平。这样一来，作者们就获得了一团包含很多空间的镍丝网。
Into these voids went the battery material, either nickel-metal hydride (NiMH) or a lithium-treated manganese dioxide. The arrangement provides three major advantages, according to the authors: an electrolyte pore network that enables rapid ion transport, a short diffusion distance for the ions to meet the electrodes, and an electrode with high electron conductivity. All of these make for a battery that acts a lot like a supercapacitor when it comes to charge/discharge rates.
这些空间将用来填充电池材料，可以是镍金属氢化物，也可以是掺杂锂的二氧化锰。作者称这种布局具备三大优点：电镀网孔有利于离子的快速运动，离子到达电极的距离缩短，电极导电性提高。这些优点的叠加使得做出来的电池在充放电速度上可以与超级电容相媲美。
With the NiMH battery material, the electrodes could deliver 75 percent of the normal capacity of the battery in 2.7 seconds; it only took 20 seconds to recharge it to 90 percent of its capacity, and these values were stable for 100 charge/discharge cycles. The lithium material didn't work quite as well, but was still impressive. At high rates of discharge, it could handle 75 percent of its normal capacity, and still stored a third of its regular capacity when discharged at over a thousand times the normal rate.
对于镍氢电池，这种电池可以在2.7秒的时间内放出标准电量的75%，而充满90%的电量只需要20秒。按这样的强度经过100次充放循环，电池性能还可以保持稳定。锂电池表现稍微差一点，但也相当了不起。标准电量的75%可以实现高速放电，而经过1000次循环后，还能保持三分之一的存储能力。
A full-scale lithium battery made with the electrode could be charged to 75 percent within a minute, and hit 90 percent within two minutes.
完全用这种电极制作的锂电池，能做到1分钟充满75%的电量，充满90%的电量只需要2分钟。
There are a few nice features of this work. As the authors noted, the electrodes are created using techniques that can scale to mass production, and the electrodes themselves could work with a variety of battery materials, such as the lithium and nickel used here. It may also be possible to merge them with the LiFePO4 used in the earlier work. A fully integrated system, with materials designed to work specifically with these electrodes, could increase their performance even further.
作者称这种技术还有其他一些优异的特性，可以实现大规模生产，除了应用于上文提到的锂材料和镍材料，它可以应用于更多的电池材料。先前的磷酸铁锂材料也能结合采用这种技术。通过专门设计，使电池材料与这种电极匹配，可以进一步提升电池性能。
Of course, that ultimately pushes us up against the issue of supplying sufficient current in the short time frames needed to charge the battery this fast. It might work great for a small battery, like a cell phone, but could create challenges if we're looking to create a fast-charge electric car.
当然，使用这么高的速度给电池充电，我们最终不可避免将面临提供大电流的问题。对于类似手机上使用的小电池来说，这样快速充电表现优异，但是如果想用于对电动汽车快速充电，那将是一项挑战。
http://article.yeeyan.org/view/211199/182436
http://arstechnica.com/science/n ... -in-two-minutes.ars