A Deep Dive On Battery Life

July 28, 2023 by Bryan Cockfield 12 Comments

There are all kinds of old wives’ tales surrounding proper battery use floating around in the popular culture. Things like needing to fully discharge a battery every so often, unplugging devices when they’re fully charged, or keeping batteries in the fridge are all examples that have some kernel of truth to them but often are improperly applied. If you really want to know the truth about a specific battery, its behavior, and its features, it helps to dig in and actually take some measurements directly like [Tyler] has done with a vast array of embedded batteries in IoT devices.

[Tyler] is a firmware engineer by trade, so he is deeply familiar with this type of small battery. Battery performance can change dramatically under all kinds of scenarios, most important among them being temperature. But even the same type of battery can behave differently to others that are otherwise identical, which is why it’s important to have metrics for the batteries themselves and be able to measure them to identify behaviors and possible problems. [Tyler] has a system of best practices in place for monitoring battery performance, especially after things like firmware upgrades since small software changes can often have a decent impact on battery performance.

While working with huge fleets of devices, [Tyler] outlines plenty of methods for working with batteries, deploying them, and making sure they’re working well for customers. A lot of it is extremely useful for other engineers looking to develop large-scale products like this but it’s also good knowledge to have for those of us rolling out our own one-off projects that will operate under battery power. After all, not caring for one’s lithium batteries can have disastrous consequences.

Better Battery Management Through Chemistry

October 7, 2019 by Bob Baddeley 33 Comments

The lead-acid rechargeable battery is a not-quite-modern marvel. Super reliable and easy to use, charging it is just a matter of applying a fixed voltage to it and waiting a while; eventually the battery is charged and stays topped off, and that’s it. Their ease is countered by their size, weight, energy density, and toxic materials.

The lithium battery is the new hotness, but their high energy density means a pretty small package that can get very angry and dangerous when mishandled. Academics have been searching for safer batteries, better charge management systems, and longer lasting battery formulations that can be recharged thousands of times, and a recent publication is generating a lot of excitement about it.

Consider the requirements for a battery cell in an electric car:

High energy density (Lots of power stored in a small size)
Quick charge ability
High discharge ability
MANY recharge cycles
Low self-discharge
Safe

Lithium ion batteries are the best option we have right now, but there are a variety of Li-ion chemistries, and depending on the expected use and balancing and charging, different chemistries can be optimized for different performance characteristics. There’s no perfect battery yet, and conflicting requirements mean that the battery market will likely always have some options.

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Battery Basics – Choosing A Battery For Your Project

December 16, 2014 by Matt Freund 30 Comments

If choosing a rechargeable battery for your project intimidates you, [Afroman] has prepared a primer video that should put you at ease. In this tutorial for battery basics he not only walks you through a choice of 5 rechargeable chemistries and their respective tradeoffs, but gives a procedure that will allow you to navigate through the specs of real-world batteries for sale – something that can be the most intimidating part of the process.

You cannot learn everything about batteries in 9 minutes, but watching this should get you from zero to the important 80% of the way there. Even if your project does not give you the specs you need to begin buying, [Afroman] tells you what to measure and how to shop for it. In particular, the information he gives is framed in the context you care about, hopefully ensuring you are not waylaid by all the details that were safe to ignore. If this is not enough, [Afroman]’s prequel video on battery terminology has more detail.

Much like your high school English teacher told you, you need to know the rules before you can choose to break them. Many of battery absolute Dos or Don’ts are written for the manufacturer, who provides for the consumer, not the hacker. Hackaday has published hundreds of battery articles over the years; search our archives when you are ready for more.

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Extending The Battery Life Of LED Dominoes

April 26, 2011 by Mike Szczys 6 Comments

[Fede.tft] wrote in to tell us about some work he’s been doing to save battery life for LED dominoes. He originally got the idea after reading this post about the electronic gaming pieces. That project was aimed at the 555 timer contest and therefore, used a 555 timer. [Fede.tft] calculates the battery life for the CR2302 battery in the 555 circuit at no more than about 80 days. That’s if you never use them and the LEDs are never illuminated. It makes sense to remove the batteries from the device when not in use, but a redesign to increase efficiency is definitely worth the effort.

This rendition does away with the 555 chip in favor of a CMOS chip. By building a circuit around four NAND gates of a CD4011 chip, the standby lifetime of the battery is calculated to increase to about 4.5 years. Not bad! Add to this the fact that replacing the 555 timer didn’t increase the component count, the price for the chip is similar to the 555, and you didn’t need to resort to a microcontroller. Yep, we like it.

Sleepy Arduino Saves Batteries

August 13, 2009 by Caleb Kraft 23 Comments

06_11 (Custom)

Battery life is often overlooked when building projects, especially for beginners. This tutorial takes you through the setup of power saving modes for the Arduino. Utilizing the watchdog and sleep functions, they put the chip into a hibernation mode between cycles. An optimum configuration could take your battery life from 4 days to about 3 years. For a lot of you, this is old news. But for the rest, this is really good stuff. You can download a sample application from the site that mimics the singing of a nightingale when the sun goes down.

Maximize The IPhone 3G’s Battery Life

July 17, 2008 by Kimberly Lau 21 Comments

Gizmodo has posted a guide for extending the battery life of your shiny new iPhone 3G. Apple is notorious for pushing products with unimpressive battery life, and the new iPhone is no different. The battery isn’t user-replaceable, which means you can’t keep a spare, and the energy needs of the 3G chipset adds to the problem. Apple provides some useful tips on maximizing battery life for your iPhone. The tips include common sense advice that applies to nearly all electronic devices – turning down the brightness on your LCD screen, turning off radios not in use like Bluetooth, WiFi, GPS, and 3G, and setting Auto-lock to a minute or less will keep your devices running smoothly for longer.