Solar energy is becoming more and more popular as prices drop, yet a home powered by the Sun isn't free from the grid¹ because solar panels don't store energy for later. Now, researchers have refined a device that can both harvest and store solar energy, and they hope it will one day bring electricity to rural and underdeveloped areas.

随着价格的降低，太阳能越来越受到大众的欢迎，但太阳能供电的家庭仍离不开电网，因为太阳能电池板并不能储存能量以备后用。现而今，研究员改进了一个设备，既可以获得太阳能又可以储存太阳能，他们希望有朝一日能为农村地区和欠发达地区供电。

The problem of energy storage has led to many creative solutions, like giant batteries. For a paper published today in the journal Chem, scientists trying to improve the solar cells themselves developed an integrated battery that works in three different ways. It can work like a normal solar cell by converting sunlight to electricity immediately, explains study author Song Jin, a chemist at the University of Wisconsin at Madison. It can store the solar energy, or it can simply be charged like a normal battery.

能量存储问题带来了多种创造性的解决方案，比如巨型电池。今日在《化学》杂志发表的一篇文章中，试图自行提高太阳能电池的科学家开发了一种集成电池，这种电池可以三种不同的模式工作。它可以像普通的太阳能电池一样立刻将太阳光转为电，研究作者Song Jin解释道，他是威斯康星大学麦迪逊分校的一名化学家。这种电池可以存储太阳能，也可以像普通电池一样充电。It's a combination of two existing technologies: solar cells that harvest light, and a so-called flow battery. The most commonly used batteries, lithium-ion, store energy in solid materials, like various metals. Flow batteries, on the other hand, store energy in external liquid tanks.

这一电池结合了两种现有技术：捕获太阳光的太阳能电池以及一种所谓的液流电池。最常用的电池--锂离子电池--将能量存储于固体材料，比如各式各样的金属。而液流电池却将能量存储于外部的液体罐中。

This means they are very easy to scale for large projects. Scaling up all the components² of a lithium-ion battery might throw off the engineering, but for flow batteries, "you just make the tank bigger," says Timothy Cook, a University at Buffalo³ chemist and flow battery expert not involved in the study. "You really simplify how to make the battery grow in capacity," he adds. "We're not making flow batteries to power a cell phone, we're thinking about buildings or industrial sites.

这就意味着，这种方法可被拓展至大型项目中。加大锂离子电池的所有组件可能会摆脱工程技术，但对于液流电池而言，'只需让液体罐更大即可，'蒂莫西·库克说道，他是布法罗大学的一名化学家，也是一位液流电池专家，并未参与这项研究。"真的简化了扩大电池容量的方法，"他补充道。"我们制作液流电池并不是为了给手机供电，我们想的是为大厦或工业用地供电。"

Jin and his team were the first to combine the two features. They have been working on the battery for years, and have now reached 14.1 percent efficiency. Jin calls this "round-trip efficiency" - as in, the efficiency from taking that energy, storing it, and discharging it. "We can probably get to 20 percent efficiency in the next few years, and I think 25 percent round-trip is not out of the question," Jin says.

Jin和他的团队是将这两种功能结合起来的'第一人'。多年来，他们一直在研究电池，现在他们所研究的电池已达到14.1%的效率。Jin将其称为'往返效率'--获取、存储和释放能量。"接下来的几年，我们或能将电池提高到20%的效率，我认为25%的往返效率也并非不可能，"Jin说道。