From the Toolbox: Batteries
A key component in most electronic devices is batteries. To put it simply, you would not have an electronic device without batteries; they are an essential element. Because we always like to provide a little historical context, the first battery was developed by Italian physicist Alessandro Volta in the year 1800. This battery contained copper and zinc, and had wires connected at both ends to produce a current. About 50 years later, the first rechargeable battery was invented. Technology has only continued to develop, and the batteries you see today are much smaller and more efficient than their predecessors.
Types of Batteries and Composition
There are so many batteries to choose from; alkaline, lithium, lithium-ion, aluminum, and the list goes on. For the sake of this article, we are going to focus on batteries used in e-textiles and prototypes. For our clients at Loomia, we offer a custom battery pack that meets the necessary power requirements of the specific project. However, the typical e-textile battery consists of lithium polymer chemistry. Sparkfun has a great rundown of how LiPo batteries are made.
There are several other sub-categories of batteries on the market, as well: textile-based batteries, flexible batteries, rechargeable batteries, and coin cell batteries are among the most popular used by creative techs and engineers. Here is a quick breakdown of each type and their applications:
TEXTILE-BASED BATTERIES
Textile-based batteries are a relatively new invention and are still in the experimentation phase of development. However, they are a promising solution to the bulky batteries that some wearable electronics possess. Some textile-based batteries contain lithium-ion chemistry, whereas others contain a graphene-oxide ink mixture and are printed directly onto the desired material. Which one is used depends entirely on the application.
FLEXIBLE BATTERIES
Back in 2018, engineers at Columbia University began developing flexible lithium batteries for wearable electronics. These batteries are an interconnected “spine” of copper, lithium, graphene, and aluminum. Because of the chain-like construction of this flexible battery, it is bendable, twistable, and has a high energy density. This battery is being developed in hopes of advancing the commercialization of e-textiles and other wearables.
RECHARGEABLE BATTERIES
Most rechargeable batteries come in the form of a battery pack and contain a USB-A port for connection to devices. The standard 5V battery pack that we would use with our prototyping parts contains a lithium-ion battery, charging circuit, and boost converters. Rechargeable battery packs are recommended for any application that requires extended use, such as electronic devices that will drain energy quickly.
COIN CELL BATTERIES
Coin cell batteries, also known as button cell batteries, are a small lightweight battery that are sometimes made with a combination of lithium, zinc, alkaline, and manganese. They are ideal for devices that require a lower power. It is important to keep in mind that coin cells are not rechargeable and cannot be reused.
Best Batteries for Prototyping
As for electronics prototyping, we recommend using a multi-cell battery pack, a coin cell battery, or a LiPo battery. Multi-cell battery packs are best for consumer electronics that require charging. If you don’t want the batteries to be removed, it is best to use an off-the-shelf battery pack. A coin cell battery is best for smaller prototypes and is very accessible and easy to work with, and LiPo batteries are similar in the sense that they are best for smaller-sized applications. All are compact solutions that provide great flexibility for wearable devices.
Shop these batteries from Sparkfun and Adafruit:
Keeping the Environment in Mind
It is more important than ever to keep the environment in mind when prototyping with electronics. Obviously, the most sustainable power solution is a rechargeable battery. According to an article from Grist, a low self-discharge nickel-metal hydride (NiMH) battery is the most eco-friendly. NiMH batteries are best for handheld devices and contain fewer toxic ingredients than other batteries on the market. While LiPo batteries are the most popular of all, they are not the best for our planet. Lithium comes from a process called water-mining which takes a tremendous amount of water and toxic chemicals to process. The only way we can make LiPo batteries fit in with a more sustainable future is to establish a comprehensive battery recycling system. Several companies, including Tesla and Northvolt, are working hard to find new ways of recycling and re-purposing old lithium batteries.
If you want to get really crafty, there are some great tutorials out there on the web for making your very own batteries. It may sound like a large undertaking, but it can be fairly straightforward depending on the battery you are making. Below are some cool battery-related tutorials from Instructables that we recommend checking out!