Choosing the correct battery type for your project is very important, read on to learn how!

It’s easy to get lost in the details when you want to use batteries to power your project, especially if you have little to no experience with them. There are many different options you can choose from, and the entire topic itself is quite complex.

In this article, I’ll provide you with a short overview of the most popular battery types and their properties so that you can more easily determine what battery type is the right one for your project.

Check out the end of this article for a clear-cut chart comparing the different battery types we’ll be discussing in detail.

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Rechargeable vs. Non-Rechargeable batteries

Non-Rechargeable batteries are also known as primary batteries. These are cheap, maintenance-free, and have a long storage time. Furthermore, they are safe to work with and readily available. Alkalines are the most popular primary battery, but they are, however, only really useful in low current applications due to their high internal resistance.

Rechargeable batteries are also referred to as secondary batteries, and they play an important role in our lives today. They are, as the name suggests, rechargeable, and they can deliver much more current compared to primary batteries. However, they are also more expensive and it’s usually impractical to utilize them in applications that draw occasional power over a long period of time.

Primary Battery Types and Properties

As mentioned above, the most popular primary battery is alkaline. These batteries have very low self-discharge, which results in a long shelf-life. While they are not fully leak-proof, alkaline batteries usually don’t leak electrolyte when they are fully depleted. They can provide reasonable power. However, that’ll discharge them rapidly, so it’s best to use these batteries in applications that draw little current over a long time.

Zinc-carbon batteries are the predecessor of alkaline batteries. They are cheaper than alkalines, which is the reason that they are still relevant. This type of battery can deliver less power, and it doesn’t hold as much charge as an alkaline.

Lithium-iron-disulfite batteries are a modern replacement for alkaline batteries. They offer lower internal resistance and can deliver more power than alkalines. However, they also more expensive and harder to find.

Secondary Battery Types and Properties

Lead-acid batteries are the oldest and cheapest of the secondary battery types. They're rugged and can withstand a lot of use and abuse. However, they have low specific energy and a limited cycle count. Furthermore, they can’t handle deep discharges well, and it can take up to several hours to recharge a lead-acid battery. Additionally, these batteries are usually quite heavy.

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Nickel-Cadmium (NiCd) batteries have a long service life, and they're able to deliver high discharge current. They can be charged very quickly, and those two properties make them perfect for use in power tools.

Nickel-metal-hydride (NiMH) batteries have the same properties as NiCd batteries. However, they are less toxic. NiCd and NiMH both have a high rate of self-discharge, which is the highest when the batteries are fully charged.

Lithium-ion (Li-ion) batteries can deliver a lot of power and can be charged fairly quickly. However, you must always use them in combination with a protection circuit to make sure they are neither charged nor discharged too much. Li-ion batteries come in many different types, named by their active materials.

When Should I Use What Battery?

Primary batteries should be used whenever it’s impractical to recharge a battery and cost is an important factor. They are suitable for low current applications that require a long battery life.

They often have a long shelf-life with low self-discharge. Primary batteries are suitable for applications that draw occasional power over a long period, but replacing them can get expensive when they are in continuous use. Some devices that use primary batteries are pacemakers, toys, remote controls, and animal trackers.

Secondary batteries should be used in applications that draw a lot of current over a short period and when it’s more economical to buy and recharge a battery several times instead of using disposable batteries.

Depending on the battery type, rechargeable ones can be quite expensive. A protection circuit is also needed in many cases, which can further increase the price. Typical applications are electric wheelchairs, golf cars, and emergency lighting (lead-acid), power-tools, and medical devices (NiCd, NiMH), and many consumer devices (Li-Ion).

What is the Best Type of Battery?

There are many different types of batteries out there, and this article should give you a rough idea of what battery might be the right one for your project. Primary batteries are usually cheap, have a low self-discharge rate, and can not deliver much power at once. However, they are great for low-power applications.

Rechargeable batteries, however, are usually capable of outputting a lot of current at once. But they are also more expensive, and protection circuitry is often needed. The following table summarizes the most important aspects of the discussed battery types.

Battery Comparison Chart

Zinc-Carbon
Alkaline
Lithium-iron-disulfite
Lead Acid
NiCd
NiMH
Li-ion*
Cost
Very Low
Low
Moderate
Low
Moderate
Moderate
High
Power
Low
Low
Moderate
Moderate
High
High
Very High
Internal Resistance
High
High
Very Low
Very Low
Very Low
Low
Very Low to Moderate
Charge Cycles
N/A
N/A
N/A
200
1000
400
500-2000
Charge Time
N/A
N/A
N/A
Very High
Very Low
Moderate
Low
Discharge Tolerance
N/A
N/A
N/A
Very Low
Low
Low
Very Low
Overcharge Tolerance
N/A
N/A
N/A
High
Moderate
Low
Low
Self-discharge
Low
Very Low
Very Low
Low
Moderate
High
Low
Usual Cell Voltage
1.5 V
1.5 V
1.5 V
2 V
1.2 V
1.2 V
3.2 V - 3.6 V
Maintenance Requirement
None
None
None
Low
Moderate
Moderate
None
Safety Requirement
Air vents
Air vents
Air vents
None
Fuse Protection
Fuse Protection
Protection Circuit

* depends on the exact active material (eg Cobalt)

Daniel Hertz
Hi! I am a software engineer and owner of nerdhut.de who loves to experiment with electronics, gadgets and tech in general.