Understanding the Difference Between NiCad and NiMH Battery Cells

Given just how popular rechargeable batteries have become in recent times, lots of people are interested to know the difference between NiCad and NiMH cells – two of the most popular choices. Broadly, the differences between the two cells can be classed in regards to their impact on the environment, overall capacity, and memory effect. NiMH batteries have a higher capacity than NiCad cells and can power your devices for longer. But how else are they different? Let’s take a look at each battery in more detail now. 

Nickel-Cadmium Batteries (NiCad) 

First developed in Sweden in 1899, NiCad batteries have been around for a while, although the modern cells are a far cry from those first established. In terms of its composition, a NiCad battery has the following: 

• Nickel (III) 
• Oxide-hydroxide positive electrode plate 
• Cadmium negative electrode plate 
• Separator 
• Potassium hydroxide electrolyte 

Widely used and popular, NiCad batteries can be found in various toys, a broad range of commercial and industrial products, power tools, and even medical equipment. They’re popular because they’re relatively cheap, simple to charge, and easy to store. They can also take a high number of charges and do well at low temperatures. 

On the flip side, they’re not the most powerful rechargeable batteries out there and they contain toxins that are harmful to the environment. Also, if you keep them in storage for too long, they will initiate self-discharge.

Nickel-Metal Hydride Batteries (NiMH) 

Almost 90 years after the emergence of NiCad batteries, NiMH cells were cleared for use in 1987. They underwent significant research and testing in Switzerland before being cleared, and they are composed in the following way: 

• Nickel hydroxide positive electrode plate 
• Hydrogen ion negative electrode plate 
• Separator 
• Alkaline electrolyte (e.g. potassium hydroxide)

NiMH batteries are commonly used in automotive batteries, mobile phones, cameras, and a range of low-cost consumer devices such as electric toothbrushes. Opting for a NiMH battery is ideal because it’s a high-capacity rechargeable battery that doesn’t overcharge. It is also free from hazardous chemicals including mercury and lead. 

However, they’re more NiMH cells are more expensive than other rechargeable batteries, and they cut power suddenly, as opposed to a trickle-down effect. Still, they’re preferable to NiCad batteries, which is reflected in the price. 

If you’re looking for rechargeable batteries for your workplace or any type of application, we specialise in custom battery pack manufacturing at AceOn, and would be delighted to assist you. Give our Telford HQ a call on 01952 293 388 and we will be very happy to help you out.