Three and a half reasons to use disposable batteries

Anybody with the desire to save the planet from overheating had better give up flying, eating meat, driving gas-guzzling cars and – wait for it – using disposable batteries. Needless to say, when I wrote about the launch of Digitec’s new batteries in a recent article, the outcry was suitably huge. Here’s a typical example of the indignation on show:

Yes, rechargeable batteries really are a good choice in many scenarios. You should use them whenever you can. Personally, I’m still using the Pale Blue varieties I tested in 2022.

That being said, there are some scenarios where disposable batteries are superior to their rechargeable cousins.

1. For long-term storage

The most common type of disposable batteries are alkaline manganese cells, or alkalines for short. Alkalines discharge less than rechargeable batteries when they’re not in use. As a result, they’re the better option if you’re stocking up for an emergency. If the worst comes to the worst, you’ll be able to use your torch or pocket radio, and won’t be left with a bunch of empty batteries you can’t charge.

2. For more voltage

Alkaline batteries generally have a higher nominal voltage than rechargeable ones. It’s around 1.5 volts in AA batteries. Rechargeable varieties made of nickel-metal hydride (NiMH) or nickel-cadmium (NiCd) are weaker in this respect, delivering a nominal voltage of about 1.2 volts. If you use devices requiring a minimum voltage, disposable batteries are sometimes better. The flipside is that alkaline batteries also lose voltage as they discharge. The voltage curve can vary greatly depending on the manufacturer.
However, you can now get rechargeable batteries that deliver a high initial voltage too. These generally work with lithium-ion technology.

3. For long-term use

Alkaline batteries may also be the better choice for devices that are rarely used or don’t need much power. Typical examples include your TV remote, alarm clock, weather station or remote for the garden sprinklers. While rechargeable batteries often give up quite quickly in these scenarios, traditional batteries generally hold their charge better and for longer. They’re also less susceptible to fluctuations in temperature.

4. For (short-term) savings

Okay, this argument only applies if you don’t take the entire lifetime of a rechargeable battery into account. Still, people who shy away from making big initial investments might tend towards buying disposable batteries. Not only do you need to fork out more for rechargeable batteries, but you also need a charger. Despite this, you usually recoup your high investment after a few uses. With this in mind, my fourth argument in favour of single-use batteries only gets a half point.

Any batteries are more expensive than mains electricity

Either way, batteries of any kind do have one serious drawback – the electricity they supply is incredibly expensive compared to mains electricity. In fact, each watt produced by a battery costs up to 300 times more. You can reduce this figure by going for rechargeable batteries. Devices with a built-in rechargeable battery are more cost-effective than ones requiring replaceable batteries.

Their energy balance is similarly negative. When they’re produced, batteries generate between 40 and 500 times more energy than they later provide during use. At least swapping single-use batteries for rechargeable alternatives can save half a kilogramme of carbon dioxide per hour of battery use.

Batteries are a hassle to recycle

Used household batteries are classed as hazardous waste. Older batteries often still contain harmful heavy metals such as cadmium and mercury. Fortunately, in Germany, Austria and Switzerland, a very high proportion of batteries really do end up at designated collection points. According to the industry organisation Inobat, the Swiss figure reaches around 80% (website in German) – the highest rate in the world. In part, this is probably down to the fact that retailers who sell batteries are obliged to take them back. Or is it all thanks to the Battery Man?

Batteries that are handed in have to be painstakingly sorted. After that, some of them are shredded and separated into individual components in specialised recycling plants. The aim? To recover valuable raw materials such as lead, iron, cobalt, lithium, nickel, manganese and zinc. This generally takes less of a toll on the environment than dismantling them from scratch.

Difference between beliefs and action

To wrap up, let’s revisit the comments made about Digitec’s new disposable batteries. It’d be fair to conclude that no sane person should or would want to buy such batteries, be it from Digitec or other manufacturers.

Our sales figures, however, show that instead of rechargeable batteries topping the rankings, it’s single-use varieties. Maybe one or two people top up their shopping cart with them in order to avoid the minimum order surcharge. But that’s probably not the main reason.

No, it’s more likely to be a case of cognitive dissonance. In many areas of life, we have firmly held beliefs. For instance, that rechargeable batteries are superior and that no one out there could possibly still think disposable batteries are good. When these beliefs collide with reality (in this case, Digitec’s recently launched disposable batteries), social psychologists say an uncomfortable sense of tension arises within us. We fight to rid ourselves of this dissonance. As a result, we might make a conscious effort to buy a couple of rechargeable batteries. Or angrily comment on articles about disposable batteries.

A similar phenomenon takes place in supermarkets in relation to food packaging. Everybody clutches their pearls when a cucumber comes in cellophane wrapping or oranges come in plastic netting. The fact that cucumbers lose their freshness more quickly without the wrapping or that cardboard packaging requires more resources in production, is heavier and therefore emits more CO₂ during transportation, however, are ignored. Contrary to the facts, this has led supermarkets to pack items in cardboard instead of more environmentally friendly plastic. Simply because customers aren’t prepared to question their beliefs and don’t want to be patronised.