Can We Mix Batteries & What Happens When We Do?

Mixing different types of batteries in electronic devices can affect battery performance. Discover the disadvantages and risks of battery mixing.

charging cables
rechargeable batteries
24.08.2023

Understanding the risks of mixing different types of batteries such as mixing rechargeable lithium-ion batteries and alkaline batteries can help to avoid any unnecessary risks to yourself and your devices. But what happens when you do mix them? Read on to discover the potential dangers of mixing different battery types and what you should do to avoid them instead.

There’s no doubt batteries have become an essential part of our daily lives. They’re used for so many different things but most importantly, they power the devices that we depend on every day. But what happens when you mix different types of batteries? Can you do it? Is it a safe practice and what are the consequences?

This article aims to shed light on one of the most seemingly unassuming acts that many people do in their day-to-day lives — mixing batteries.

Can We Mix Batteries?

So, can you mix different types of batteries?

In general, it is never recommended to mix different types of batteries — whether they’re old or new, used in electric vehicles, or are of a different group size. The reason is simple, different types of batteries come with different voltages, capacities, chemistries, and amperage ratings. And when you mix batteries, you can potentially create a dangerous situation. For example, say you use an AA battery with an AAA battery. The former typically comes with a higher voltage compared to the AAA battery. Using them in tandem can cause the AAA battery to overheat, which can potentially explode.

Let’s consider another common scenario: can you mix rechargeable lithium batteries with regular batteries? No, that isn’t recommended either.

Typically, rechargeable batteries comprise lithium or nickel-metal hydride (NiMH) 2and have a specific voltage/capacity rating. On the other hand, non-rechargeable regular batteries are usually alkaline batteries while also having different voltage/capacity characteristics. When you mix them with one another, a scenario where a mismatch in voltage and discharge rates can potentially be created. This could lead to a number of potential problems (which we will cover in the following section), the worst of which is damage to the devices that they power.

What Happens When We Mix Batteries?

When you mix different types of batteries used in many ways such as in common household appliance remote controls or even in electric vehicles, you may come across a number of different problems such as:

Overcharging or undercharging of the batteries

Mixing batteries, especially batteries with different voltages and capacities, can lead to imbalances in charging. This could then result in overcharging or undercharging of the batteries which subsequently leads to reduced battery life and performance. Even mixing old and new batteries is not suggested as this can lead to the same issue.

Reduced battery life

Likewise, batteries that you commonly use come with different chemistries or capacities and mixing them means you could potentially affect the overall life of the battery. Different types of batteries may discharge at different rates, leading to an uneven distribution of power and can cause a shorter lifecycle altogether.

Increased risk of fire or explosion

This is one of the worst-case scenarios when mixing batteries, especially rechargeable and non-rechargeable alkaline or single-use batteries. The variations in chemical reactions in the batteries can potentially cause unpredictable and dangerous reactions when combined.

Damage to electronic devices

Each device that uses batteries is typically designed to work with a specific range of battery voltages. Using mismatched batteries could potentially overload the circuits and cause malfunctions in the device. Thus, it would be better to follow the manufacturer’s recommendations when it comes to picking batteries to use.

What Should We Do Instead?

To ensure optimal performance and safety, it is best to use batteries of the same type and rating when you can. This means not using batteries of different brands together. But if you really must, make sure to check and compare so that the type and ratings are similar or as close as possible. This is to avoid power distribution imbalances and reduce the likelihood of overcharging or undercharging.

Additionally, it is also a good idea to consult the manufacturer’s instructions for the device you’re using if you’re still unsure. Manufacturers often include specific instructions or recommendations for battery types to achieve optimal performance and safety so following these guidelines will help you decide which batteries are more suited for that specific device to meet its power requirements.

In closing, using different types or brands of batteries together can result in reduced performance of the battery at best and can be highly dangerous at worst. Therefore, it is best to opt for batteries of the same type, brand, and group size wherever possible. By adhering to this simple tip, you save yourself a lot of headaches and problems in the long run. More importantly, you can keep yourself and your devices safe!