Why your phone battery gets worse over time - George Zaidan

翻译人员: Ryan Qiao 校对人员: suya f.

A drop of gasoline, a match, and a battery, all store energy—

一滴汽油，一根火柴， 和一节电池，都储存着能量 ——

but, after each expends its energy, only the battery is recyclable.

但是，当它们的能量耗尽之后， 只有电池可以被回收利用。

That's because, chemically speaking,

这是因为从化学角度来讲，

a dead battery is actually not that different from a fresh one.

一块用完的电池实际上 和一块新的区别不大。

Most of the batteries we use today take advantage

我们今天使用的大多数电池，

of the fact that some metals like to release electrons

都利用了一些金属喜欢释放电子，

and others like to accept them.

而另一些金属喜欢接收电子的特性。

For example, in a typical alkaline double-A battery,

例如，在一个常见 的碱性AA电池中，

zinc metal reacts with hydroxide ions,

锌金属与氢氧离子发生反应，

changing into zinc oxide and releasing electrons at the negative terminal.

转化为氧化锌， 并从电池负极释放电子。

The electrons travel through, say, a light bulb,

电子穿过灯泡之类的用电器，

and then return to the battery at the positive terminal,

然后回到电池正极，

where they’re accepted by manganese dioxide.

被二氧化锰接收。

Different batteries use different combinations of metals,

不同的电池使用不同的金属组合，

and sometimes non-metals like graphite,

有时还有非金属，比如石墨，

but the basic idea is to use a pair of chemical reactions

但基本原理都是利用一对化学反应

to generate a stream of electrons.

来产生电子流。

Almost all batteries, even single-use batteries,

几乎所有电池，即使是一次性的，

are theoretically rechargeable.

从理论上讲都是可以重复充电的。

That's because the metals and other chemicals are still right there.

这是因为那些金属 和其他化学物质仍然存在。

That’s very different than in, say, gasoline,

这与汽油释放能量的原理大不相同。

where the liquid hydrocarbon molecules are converted to gases.

燃烧汽油时， 液态烃分子转化为气体。

You can't convert exhaust back into gasoline,

我们无法将尾气转换回汽油，

but, with some work you can convert, say, zinc oxide back to zinc.

但我们可以使用一些方法， 将氧化锌转化回锌。

So then what's the difference between these and these?

那么，这两种电池之间 有什么区别呢？

The short answer is that trying to recharge a single-use battery

简而言之，当我们尝试 给一次性电池充电时，

doesn’t just force these reactions to run in reverse.

结果并不仅仅是逆转了 放电的化学反应，

It also results in a bunch of side reactions that produce

还会引发一连串的副反应，

useless contaminants,

产生无用的污染物，

reducing a battery’s capacity;

损害电池的容量；

and it could even damage the internal structure of the battery,

甚至可能损坏电池的内部结构，

leading to a loss of electrical contact and failure.

形成断路导致电池失效。

Rechargeable batteries are engineered to avoid these issues.

可充电电池的设计 就避免了这些问题。

Look at this lithium-ion battery.

我们来看这个锂离子电池。

Both sides have an atomic-level structure that you can imagine as lots of docks.

它的两端都有一种原子级的结构。 你可以把它们想象成很多码头。

So when the battery is powering something,

当电池为某个设备供电时，

the lithium “ships” give up their electrons to power the circuit,

锂“船”给出他们的电子来供电，

and then sail over to the other side of the battery,

然后航行到电池的另一端，

dock in an orderly, organized way,

以有序的方式停靠，

and meet up with their now-lower-energy electrons.

并与它们现在能量 变低了的电子汇合。

When the battery is being charged, the opposite happens.

当电池充电时，情况相反。

Over the course of hundreds, sometimes thousands, of charge cycles,

在成百上千次的供电和充电循环中，

some of the lithium ion ships sort of veer off course

一些锂离子船会偏离原来的航线，

and engage in side reactions,

参与副反应，

producing stuff that increases the internal resistance of the battery,

产生增加电池内部电阻的物质，

which in turn makes it lose efficiency and power

进而损失电池的效能和功率，

until it inevitably dies.

直至电池不可避免地完全失效。

Even when that happens, you can bring dead batteries back to life—

即便是这样，我们也可以 通过回收的方式使电池起死回生 ——

whether they’re rechargeable or not— by recycling them.

无论它是可充电的还是一次性的。

The heart of most battery recycling is a process called smelting,

大多数电池回收流程的核心是冶炼，

which is basically just melting the metallic parts.

也就是将金属部分熔化。

This drives off impurities,

这样可以去除杂质，

returning metals back to their initial, orderly state.

将金属恢复到它们初始的有序状态。

Unfortunately, in many countries you can’t just toss household batteries

遗憾的是，在许多国家，

in with your regular recycling.

你不能直接把家用电池随普通 的可回收垃圾丢掉。

You have to take them to a battery collection point or recycling center.

你需要把废电池带到指定 的电池回收点或回收站。

Same goes for more complicated rechargeable batteries:

对于更复杂的充电电池也是一样：

you need to bring them to a collection point

你需要把它们带到回收点，

or send them back to the company you bought them from.

或者寄回它们的卖家。

It’s a pain, but absolutely worth the time and effort,

这可能有些麻烦， 但绝对值得我们的时间和精力，

because recycling batteries is critical.

因为回收电池至关重要。

Not only does it prevent potentially toxic battery metals

这不仅可以防止有毒的电池金属

from leaking into the environment,

泄漏到环境中，

it conserves scarce— and vital— resources.

还可以保护稀缺的重要资源。

Earth has about 22 million tons of lithium—

地球上有大约2200万吨的锂 ——

enough for about 2.5 billion EVs.

足够供给大约25亿辆电动汽车。

That sounds like plenty, but it’s only 25% higher than the number of EVs

这也许听起来很多，但也只不过比

experts believe it’ll take to reach net zero emissions by 2050,

据专家推测能使2050年实现零排放 所需的电动汽车数量高出25％，

and that doesn’t even account for laptops, phones, and anything else

而这还没有算上笔记本电脑、手机

that uses a lithium-ion battery.

和使用锂离子电池的其他设备。

Currently, though, most lithium-ion batteries are not manufactured

然而，目前大多数 锂离子电池的设计和生产

with recycling in mind.

并没有考虑到回收问题。

The designs are intricate and non-standard,

它们的设计繁复而缺乏统一标准，

and the components are held together by almost indestructible glues.

组件也被胶粘剂牢固地粘在一起。

So today, less than 5% of lithium-ion batteries are recycled.

因此，目前只有不到5%的 锂离子电池能够得到回收。

Regulations that clearly define who is responsible for a spent battery

明确定义废电池回收的 责任方和回收方法的规章制度

and what should happen to it can boost recycling dramatically.

可以大幅提高回收率。

For example, lead-acid batteries are generally subject to stringent regulations

例如，铅酸电池通常受到 严格的法规约束，

and are recycled at much higher rates than lithium-ion batteries.

它们的回收率从而 比锂离子电池高得多。

Over the next century, we’ll need to recycle huge numbers of EV batteries,

在未来的一个世纪里， 我们将需要回收大量的电动汽车电池，

so scientists are working on making the battery recycling process cheaper

因此科学家们正在努力 使电池回收过程变得

and more environmentally friendly.

更加便宜和环保。

Smelting uses a lot of energy and, depending on the type of battery,

冶炼过程消耗大量能源， 并且根据电池的类型，

can release harmful by-products.

可能会释放有害的副产物。

In addition to regulations, industrial processes, and our own individual choices,

除了法规、工业流程和个人选择外，

battery tech will also continue to evolve.

电池技术也将继续发展。

There are proof-of-concept batteries being developed that can convert

一些可以将力、环境声、 甚至尿液转化为电力的

physical force, ambient sound, and even pee into electricity.

概念性电池正在研发当中。

But if your top priority is to make your number one source of power, number one,

但如果你想要把马桶 作为你发电的第一生产力，

sorry to say, but urine for a long wait.

那么很遗憾， 你也许要等到猴年马月了。