Why your phone battery gets worse over time - George Zaidan

譯者: 麗玲 辛 審譯者: Helen Chang

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

一滴汽油、一根火柴 和一塊電池都可以儲存能量，

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

但能量耗盡後，只有電池可回收再利用。

That's because, chemically speaking,

這是因為，從化學角度來說，

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

廢電池實際上與新電池沒有什麼不同。

Most of the batteries we use today take advantage

我們使用的多數電池 都利用了一個原理：

of the fact that some metals like to release electrons

某些金屬喜歡釋放電子，

and others like to accept them.

而其他金屬喜歡接收電子。

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

例如，在典型的鹼性AA電池中，

zinc metal reacts with hydroxide ions,

鋅金屬與氫氧根離子反應，

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

變成氧化鋅，並在負極釋放電子。

The electrons travel through, say, a light bulb,

電子經過燈泡，

and then return to the battery at the positive terminal,

然後返回電池的正極，

where they’re accepted by manganese dioxide.

在那裡被二氧化錳接收。

Different batteries use different combinations of metals,

不同的電池使用不同的金屬組合，

and sometimes non-metals like graphite,

有時也使用石墨等非金屬，

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

但基本概念都是利用一組化學反應

to generate a stream of electrons.

來產生電子流。

Almost all batteries, even single-use batteries,

幾乎所有電池，即使是一次性電池，

are theoretically rechargeable.

理論上都可充電，

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

因為金屬和其他化學物質仍在電池裏。

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

汽油就不一樣，

where the liquid hydrocarbon molecules are converted to gases.

汽油中的液態碳氫化合物分子 會轉化為氣體。

You can't convert exhaust back into gasoline,

廢氣無法轉化回汽油，

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

但是，通過一些反應， 氧化鋅可以轉化回鋅。

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

那麼，一次性電池 與可充電電池有什麼區別呢？

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

簡而言之，如果讓一次性電池充電，

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

不僅會強迫這些反應逆轉，

It also results in a bunch of side reactions that produce

還會產生大量的副反應，

useless contaminants,

產生無用的污染物，

reducing a battery’s capacity;

降低電池的容量，

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

甚至可能損壞電池的內部結構，

leading to a loss of electrical contact and failure.

導致喪失電極的接觸和故障。

Rechargeable batteries are engineered to avoid these issues.

可充電電池的設計 就是為了避免這些問題。

Look at this lithium-ion battery.

看看這個鋰離子電池。

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

兩側都有一個原子級結構， 你可以將其想像為許多碼頭。

So when the battery is powering something,

當電池正在供電時，

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

鋰「船」放棄它們的電子來供電，

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

然後航行到電池的另一側，

dock in an orderly, organized way,

以有序、有組織的方式停靠，

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

再度與能量已降低的電子相結合。

When the battery is being charged, the opposite happens.

當電池充電時，情況則相反。

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

在數百次甚至數千次的充放電週期中，

some of the lithium ion ships sort of veer off course

一些鋰離子船會偏離軌道，

and engage in side reactions,

進行副反應，

producing stuff that increases the internal resistance of the battery,

產生增加電池內部電阻的物質，

which in turn makes it lose efficiency and power

這反過來使其效率和功率下降，

until it inevitably dies.

直至最終電池失效。

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

即使如此，無論是否可再充電， 你都可以藉由回收

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

讓用完的電池再次「復活」。

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

大多數電池回收的重點是 一個叫做熔煉的過程，

which is basically just melting the metallic parts.

基本上就是將金屬部分融化。

This drives off impurities,

這可以去除雜質，

returning metals back to their initial, orderly state.

使金屬恢復到最初的有序狀態。

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

不過，在許多國家，

人們不能隨便將家用電池 投入普通的回收箱，

in with your regular recycling.

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

必須將它們帶到 電池回收站或回收中心。

Same goes for more complicated rechargeable batteries:

更複雜的充電電池也是如此：

you need to bring them to a collection point

你需要將它們帶到收集點

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

或將它們寄回售出電池的公司。

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

這可能有些麻煩， 但絕對值得花時間和精力，

because recycling batteries is critical.

因為回收電池至關重要。

Not only does it prevent potentially toxic battery metals

這不僅可以防止可能有毒的 電池金屬洩漏到環境中，

from leaking into the environment,

it conserves scarce— and vital— resources.

還可以節約稀缺且重要的資源。

Earth has about 22 million tons of lithium—

地球上約有 2200 萬噸的鋰，

enough for about 2.5 billion EVs.

足夠供應約 25 億輛 電動汽車使用。

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

這聽起來很多， 但比起專家認為到 2050 年

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

達到零排放淨量所需的 電動汽車數量只高出 25％，

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

這還不包括筆電、手機

和其他使用鋰離子電池的設備。

that uses a lithium-ion battery.

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

但目前，大多數鋰離子電池在製造時

with recycling in mind.

並未考慮到回收利用。

The designs are intricate and non-standard,

這些設計複雜且非標準化，

and the components are held together by almost indestructible glues.

組件由幾乎堅不可摧的 膠黏劑固定在一起。

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

因此，現今不到 5％ 的 鋰離子電池被回收。

Regulations that clearly define who is responsible for a spent battery

法規該明確規定誰負責處理廢電池

and what should happen to it can boost recycling dramatically.

以及應該如何處理， 這樣就可以大大促進回收率。

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

例如，鉛酸電池通常受到嚴格的監管，

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

回收率因此遠高於鋰離子電池。

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

在未來的幾十年裡，我們需要 回收大量的電動汽車電池，

so scientists are working on making the battery recycling process cheaper

因此科學家正在努力 讓電池回收過程更加便宜、環保。

and more environmentally friendly.

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

熔煉過程會消耗大量能源，

並且根據電池的類型， 可能會釋放出有害的副產品。

can release harmful by-products.

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

除了法規、工業流程 和我們個人選擇之外，

battery tech will also continue to evolve.

電池技術也將繼續進化。

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

各種的概念驗證電池已經在研發，

可以將物理作用力、環境音， 甚至尿液轉化成電力。

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

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

但如果你的首要目標是 讓你的小號作為主要能源，

sorry to say, but urine for a long wait.

抱歉，這可能還「噓」要很長的時間。