Why your phone battery gets worse over time - George Zaidan

Translator: 玥 原 Reviewer: Aubrey Cheng

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

一滴汽油、一支火柴、一粒電 全部都儲咗能量

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

佢哋嘅能量一耗盡，得電池可以循環再造

That's because, chemically speaking,

噉係因為喺化學角度嚟講

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

冇哂電嘅電池同新電池其實冇乜分別

Most of the batteries we use today take advantage

大部分我哋而家用緊嘅電池利用到

of the fact that some metals like to release electrons

某啲金屬會釋放電子

and others like to accept them.

有啲會接收呢啲電子嘅特質

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

例如，一舊典型鹼性2A電池

zinc metal reacts with hydroxide ions,

混合鋅同氫氧離子嘅化學反應

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

產生氧化鋅兼喺負極釋放電子

The electrons travel through, say, a light bulb,

電子通過，譬如係燈泡

and then return to the battery at the positive terminal,

之後去到電池嘅正極

where they’re accepted by manganese dioxide.

喺嗰度電子會俾二氧化錳接收

Different batteries use different combinations of metals,

唔同嘅電池使用唔同嘅金屬組合

and sometimes non-metals like graphite,

有時都會使用非金屬好似石墨

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

但基本上都係要利用化學反應

to generate a stream of electrons.

去產生一系列嘅電子

Almost all batteries, even single-use batteries,

幾乎所有電池甚至係一次性嘅

are theoretically rechargeable.

理論上都係可重複使用

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

因為嗰啲金屬同其他化學物質仲喺度

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

同汽油嘅原理非常唔同

where the liquid hydrocarbon molecules are converted to gases.

汽油液體成分入面嘅烴會被轉化做氣體

You can't convert exhaust back into gasoline,

廢氣就冇辦法轉返做汽油嘅

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

不過有啲物質變得返轉頭 好似氧化鋅變得返做鋅

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

噉究竟兩者有咩分別呢？

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

簡單嚟講，嘗試重新將一次性嘅電池充電

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

唔只係將剛才提及嘅化學反應調返轉

It also results in a bunch of side reactions that produce

仲會導致一系列嘅副反應，繼而產生

useless contaminants,

冇用嘅污染物

reducing a battery’s capacity;

減少電池嘅用量

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

甚至會破壞電池嘅內部結構

leading to a loss of electrical contact and failure.

導致接觸不良同電池故障

Rechargeable batteries are engineered to avoid these issues.

充電池就避免到呢個問題

Look at this lithium-ion battery.

睇吓呢粒鋰離子電池

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

兩邊都有原子水平結構， 就當佢哋好似碼頭噉

So when the battery is powering something,

因此喺電池供電嗰陣

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

鋰電子輸出電子去供電畀電路

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

之後電子游去電池嘅另一邊

dock in an orderly, organized way,

既有跌序又整齊噉泊好位

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

然後同佢哋嘅低能量電子結合

When the battery is being charged, the opposite happens.

當充電嗰陣，相反嘅過程會發生

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

喺經過幾百甚至幾千次嘅充電周期

some of the lithium ion ships sort of veer off course

有啲鋰離子會偏離航道

and engage in side reactions,

變成副反應

producing stuff that increases the internal resistance of the battery,

產生增加電池內阻嘅物質

which in turn makes it lose efficiency and power

導致電池失效同冇哂能量

until it inevitably dies.

直到粒電池完全唔用得

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

就算係噉，你仲可以令佢翻生

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

無論粒電係咪充電池，都可以回收再造

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

大多數電池回收嘅關鍵係熔化過程

which is basically just melting the metallic parts.

其實就係溶解金屬部分

This drives off impurities,

噉做會去除雜質

returning metals back to their initial, orderly state.

回復金屬嘅原始有序狀態

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

唔好彩嘅係，大部分國家

in with your regular recycling.

都做唔到定期回收家用電池

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

你必須拎去電池收集點或者回收站

Same goes for more complicated rechargeable batteries:

更加複雜嘅可充電池都係一樣

you need to bring them to a collection point

你要拎去收集點

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

或者寄返原廠

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

好麻煩，但真係值得花心機同時間去做

because recycling batteries is critical.

因為回收電池好重要

Not only does it prevent potentially toxic battery metals

唔只因為佢可以防止潛在嘅

from leaking into the environment,

有毒電池金屬污染環境

it conserves scarce— and vital— resources.

仲幫到我哋保存稀有又重要嘅能源

Earth has about 22 million tons of lithium—

地球有大約2千2百萬噸嘅鋰

enough for about 2.5 billion EVs.

足够畀25億部電動車用

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

好似好多，但只係比 現有嘅電動車數量高25%

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

專家認為噉做可以 喺2050年實現零排放

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

甚至乎未計同樣用鋰離子電池嘅

that uses a lithium-ion battery.

手提電腦、手機等其他装置

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

雖然目前，大多數鋰離子電池

with recycling in mind.

仲未被加工變成可回收嘅形式

The designs are intricate and non-standard,

個設計精密複雜、冇既定標準

and the components are held together by almost indestructible glues.

内部零件又由膠水痴實咗

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

所以而家得少過5%嘅鋰電池回收到

Regulations that clearly define who is responsible for a spent battery

監管條文清晰定義咗邊個去負責廢棄電池

and what should happen to it can boost recycling dramatically.

對佢嘅處理可以推動電池回收嘅進程

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

例如，對鉛酸電池嘅處理 一般係有嚴格規定嘅

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

仲遠遠高過鋰離子電池嘅回收率

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

喺下一個世紀， 我哋需要回收更多電動車嘅電池

so scientists are working on making the battery recycling process cheaper

因此科學家致力令回收過程價錢更平

and more environmentally friendly.

同埋對環境更有利

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

熔化需要用好多能量，仲要睇吓邊款電池

can release harmful by-products.

亦會產生好多有害嘅副產品

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

除咗法律規定、工業過程同 我哋自己嘅選擇

battery tech will also continue to evolve.

電池技術會繼續進步

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

有證據表示一啲電池概念可以將

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

外力、噪音，甚至尿液轉化成電力

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

如果你目的係想將佢變為主要能源

sorry to say, but urine for a long wait.

唔好意思，睇怕你仲有排要等