We use more and more devices. To make these devices work properly, there are all kinds of batteries on the market. Lithium-ion batteries and nickel-metal hydride (NiMH) batteries are the two types we often use. We need to compare them to know which one suits our needs. In this article, we’ll talk about the main differences between them and how to compare them.

What are NiMH batteries?

NiMH batteries are a commonly used rechargeable battery. It uses nickel hydroxide (Ni (OH) ₂) as the positive electrode and metal hydride (MH) as the negative electrode. This type of battery is a type of alkaline battery. Its electrolyte is usually a potassium hydroxide (KOH) solution. Nickel hydrogen batteries have been around since the early 1970s. People like it because of its high energy density, which is stronger than nickel–cadmium batteries and lead-acid batteries. Moreover, nickel-hydrogen batteries are environmentally friendly, durable, safe ,and reliable to use.

NiMH batteries don’t need a complex battery management system (BMS) like lithium batteries, but we’ve designed a BMS for them to help them last longer and give the same information as lithium batteries.

Where are NiMH batteries best suited?

NiMH batteries can discharge a large amount of current at once, so they’re often used in power-hungry devices. They can be a single battery or a group of batteries. For example, flashlights, portable devices, power tools, etc. are where they come in handy. NiMH battery packs are especially good for devices that are both power-hungry and demanding.

 

NiMH batteries can also be used as a backup power source because there’s a Battery Management System (BMS) to control charging and discharging, which makes the battery last longer.

Advantages and disadvantages of NiMH batteries

Advantages of NiMH batteries:

Nickel hydrogen batteries can be used on many devices because they come in common sizes like AA and AAA. There are not many active materials used to make this type of battery, so it is relatively safe to use. Even if the nickel hydrogen battery is completely depleted, it will not have a significant impact on the battery itself. Compared to lithium-ion batteries, nickel hydrogen batteries are more affordable in price.

Disadvantages of NiMH batteries:

Compared with lithium batteries, nickel-metal hydride batteries are a bit “unforgiving”. Some nickel-metal hydride batteries left unused for a month may lose half of their power, but this are mainly some specific types. The voltage of NiMH batteries is relatively low, generally only 1.2V, much lower than lithium batteries. When it comes to charging, NiMH batteries are slow, taking 8 to 12 hours to charge. If charged too quickly, the battery may break. Lithium batteries are much more powerful and can be fully charged in 3 to 5 hours, depending on the battery capacity. Nickel-metal hydride batteries are also “afraid of heat”, and when the temperature is high, the battery voltage will fall.

What is a lithium battery?

A lithium-ion battery is a battery that can be recharged many times. Its design and technology are more advanced than most batteries today. Besides carbon, it uses a lithium-ion alloy as the main electrochemical material, which allows the battery to store a lot of power while being lightweight.

 

Many things we use, like communications equipment, electric cars, and large electrical equipment and energy storage systems, use lithium-ion batteries. Customized battery packs made from lithium-ion batteries provide high voltage, a lot of capacity and high energy density.

The best applications for lithium-ion batteries

Lithium-ion batteries have high energy density, high voltage, and high capacity, which makes them popular in consumer electronics and everyday life. They can power motorcycles and golf carts, allowing these vehicles to go farther. Electric cars rely heavily on lithium-ion batteries because these batteries make the car last longer. Also, if you have an RV or a trolling boat, lithium-ion batteries can be used as RV batteries or motor batteries for your trolling boat, allowing you to be more spontaneous outdoors.

 

Advantages and Disadvantages of Lithium Ion Batteries

Benefits of lithium-ion batteries:

Lithium-ion batteries are very powerful, capable of more than 2500 mAh. They also have good voltage performance, with an average voltage of no less than 3.2 V. They’re lightweight and safe to use. The charging speed is fast and you don’t have to wait long. The self-discharge rate is low, only about 3.5% a month, so even if left unused, they won’t run out of power quickly. If used normally, these batteries can last up to 10 years. They work well even in very cold or very hot places, like between -20°C and 60°C. They’re easy to use and don’t need much maintenance.

Shortcomings of lithium-ion batteries:

Compared to NiMH batteries, lithium-ion batteries are a bit expensive.

What are the differences between NiMH and Li-Ion batteries in terms of total cost and battery pack size?

Cost:

Nickel hydrogen batteries are also inexpensive due to their low production costs. Specifically, the final production price of nickel–hydrogen batteries is less than half of that of lithium-ion batteries. When developing new products, the cost of nickel hydrogen batteries only accounts for about 75% of that of lithium-ion batteries. Although nickel–hydrogen batteries also have some regulatory and other development steps, overall, they are still much cheaper than lithium batteries.

 

 Lithium batteries have a more complex production process and higher costs. However with technological advances and large-scale production, the price of lithium batteries has been going down year by year and is gradually becoming the mainstream of the market. Still, the initial cost of lithium batteries is higher than that of NiMH batteries, which might be a concern for budget-conscious consumers.

Size:

NiMH batteries: NiMH batteries are relatively large, but their average power consumption is higher at 2200mAh. This means they may need a larger size to hold more power at the same capacity.

Li-ion batteries: Li-ion batteries are lighter and smaller, but their average power consumption is relatively low at 1500 mAh. But the high energy density of Li-ion batteries lets them store more power in a smaller size, giving them an advantage in applications that need a lightweight and compact design.

Do NiMH and Li-ion batteries last as long?

The national standard for nickel–hydrogen batteries is that they can be used up to 500 times (with a discharge depth of 80%), while some companies claim they can be used up to 1000 times. In fact, nickel-hydrogen batteries can generally last for more than 5 years. However, if nickel hydrogen batteries are overcharged, the damage to them is greater than that of nickel cadmium batteries, so the correct charging method is particularly important for extending their lifespan.

Lithium batteries: Lithium batteries are usually good at withstanding repeated charging and discharging. For example, lithium iron phosphate batteries can theoretically be used 3,000 times or more, while lithium ternary batteries can theoretically be used about 900 times. If used normally, lithium batteries can last about 10 years.

Which is safer, nickel hydrogen batteries or lithium batteries.

Nickel-metal hydride batteries are safer. The electrolyte is a non-flammable aqueous solution, the specific heat capacity is large and the energy density is low, so even if there’s a short circuit, it’s not easy to cause a fire. In a high temperature environment, NiMH batteries are more stable, not easy to overheat, and have a low risk of fire. In daily use, nickel-metal hydride batteries are more tolerant to temperature changes and less likely to cause problems.

In contrast, lithium batteries may go out of control at high temperatures or short circuits, the temperature rises sharply and releases a lot of heat and gas, which is easy to cause a fire. Lithium battery fires are big, spread fast, are hard to put out and easy to re-ignite. Although technological advances have improved the safety of lithium batteries, there are still safety risks in extreme cases, and extra care and strict safety measures are needed when using them.

Choosing the best battery for you

 

To make a good choice for your battery needs, start by understanding the benefits of NiMH and Li-ion battery packs. Look into the unique advantages of each battery chemistry for your specific application. At the same time, extend the life of your battery with a cost-effective battery management system (BMS) solution.If you want to choose a good lithium battery, Huijue Group is a good choice for you