It’s exactly a year since I’ve sketched the first Chargie schematic. I can’t believe it went so fast!
Today I’ve compiled version 1.18.06 of the app, the best so far. Now Chargie can do much more than it could back in May when version 1.0.0 came out.
I remember the first customer at Maker Faire Vienna in May – he was a very young dude, saying he’d dreamed about such a device for years – that’s what’s truly fulfilling about inventing and making stuff.
Knowing that your creation will enter people’s homes, will satisfy their needs, that some of them will be actively involved in the very core of your product’s development with their original ideas, is something few people experience in their lifetime.
It’s been an honor knowing you all from around the world. We’ve sold more than 1300 Chargies on every inhabited continent, in most of the countries where there’s a smartphone.
It’s been a good time – with real feedback, as deserved – good or bad.
Let 2020 be a year of progress for this project and let batteries live well for your entire phones’ lives.
Lithium ion battery capacities have been evolving at a steady rate in the past few years. This is driven mainly by electric cars, but also mobile phones have their share of the lithium ion market.
However, lithium resources are scarce compared to the global ambitions of Tesla, Apple or Samsung. Efforts to recycle have to be backed by efforts to preserve battery lifespan, without impacting the overall user experience.
This series of posts will talk about the different aspects that conscious phone owners have to take into account to extend their phone’s battery life, usability and recyclability.
We’ll be talking about lithium ion batteries, just because these are the norm nowadays and their environmental toll is high, which makes protecting them worth talking about.
The real life of batteries
Although in theory they should be lasting forever, in real life scenarios batteries are exposed to factors like:
temperature
humidity
mechanical shocks
electrical stress (sudden charge/discharge)
depth of discharge
trickle charging (keeping it constantly charged)
Most lithium ion battery manufacturers recommend from 300 to 500 charge/discharge cycles for their products. That is the conservative approach, which means they shouldn’t lose much capacity over that range.
Not all cycles are created equal.
They depend on the depth of discharge, time of charge and temperature. Lithium Ion units are very sensitive to the depth of discharge. The lower you go, the worse it gets for the battery. Some papers refer to cycles as a continuous charging process from zero to 100%. Others add mini-cycles (like from 30% to 50%) to this equation, but they’re not equal in terms of battery degradation.
The battery health is reflected by its capacity to store energy, measured in mAh (milliamp-hours).
Voltage doesn’t quite matter in this, as it is not linear. For example, a phone’s lithium ion battery starts from 3.2v (empty) and goes to 4.35v (full). But in between there are a lot of charging states that don’t correlate to the voltage directly.
On this matter, there’s no other authority online that has published more experiment results than battery expert Cadex, through their site batteryuniversity.com
They have published a graph that shows the degradation of a regular 1500 mAh lithium ion cell.
As you can see on the chart above, capacity heavily relies on the number of cycles. But these were full 0-100% cycles. The same scenario wouldn’t have happened if the cycles had been smaller.
In fact, not only those partial cycles would have helped, but the battery would have had much more combined activity than if it were cycled all the way through!
As you can see, at a shallow 10% DoD (depth of discharge) the number of cycles of a LiPO4 battery was dramatically increased. A living example are the batteries of 2nd-gen Toyota Prius, that still live on after 15 years. They’re being used regularly only in the interval of 50 to 75%.
Phone battery protection
But, you don’t have to do this to a phone. Phones are supposed to have a much shorter lifespan, but the user still has to enjoy its experience for as long as he wishes.
Practically, if you only charge a phone to 90% and then unplug, its lifespan will be increased to more than 5000 cycles before it shows any signs of degradation.
Chargie is a very useful tool to achieve that. Beyond first-hand usage, your old phone may get new life in someone else’s pocket, after you decide it’s time to upgrade it. A phone’s technology is usually good enough for 3-4 years, but a Chargie will protect all of your future phones, and much more.
The Chargie app sits at the core of your phone’s future battery life.
We thought about making an app that people won’t need instructions using. And we think we succeeded, but still things are clearer for everyone when they’re being laid out properly.
0. Connect the hardware
Nothing special here – just insert your Chargie stick into the regular wall charger or mobile battery and the phone in the other side of Chargie. It should sit in-between your charger and your phone.
The setup is so simple it’s almost magic.
1. Keep it on
First, you need to know that the Chargie app is essential for the stick to work. It is the one commanding the switch to turn on or off, and the one providing feedback when the battery reaches the desired level. If you kill the app, the Chargie stick will act just like a power cable, nothing more.
The system has been designed like this from the very beginning, since you don’t want your phone to not get charged should anything happen to the app.
2. Connect to a Chargie
When you start the app, it will scan for Bluetooth devices. Make sure you’ve accepted the three dialogs at the beginning, they grant the necessary rights for the app to work properly.
Then, just click the Chargie you want to use, wait for the Bluetooth icon to turn green and and pass on to the next step.
If you have more than one Chargie device in the list, a down-pointing animated arrow will appear below them. Just swipe down or click that arrow to see the whole bunch. If not used, the list will collapse to just one item after 10 seconds.
After the charge-mode Chargie is set, the app will automatically connect to it when the phone is plugged in next time. If you own multiple Chargies and the next time you use another one, you have to manually select it again. After that, it will default to the last one used.
3. Set your charge percentage
After you’ve connected, drag the battery-shaped slider to your wish. You will notice that if the current charge percentage is higher than what you set, the red LED on Chargie will turn off, and so will power to your phone.
3.1. How charging works
below 95%
Chargie fills your battery up to the percentage you chose, waits for it to drop 1% and then restarts charging.
You can charge up to whatever value you wish, and it’s best if you charge from 70 to 85%.
above 95%
There are days when you know you’ll need the full battery. Just set the threshold to 100% (or above 96%) and Chargie will still do a better job than if you hadn’t used it:
It just goes to 100% and then performs a hysteretic charge. What that means is it lets the phone discharge down to 95% and then recharges again. The discharge normally happens very slowly during the night, since it’s being done with the screen off. This lets the battery cool down to room temperature and doesn’t add stress to it, like a normal charger would by constantly topping it up to 100%.
All of this should keep the battery happy and less stressed that normal, which surely guarantees longer lifespan and a more satisfying overall user experience.
4. How to forget a device
Method A.
There are times when we want to delete things from our list. While connected to a device, just click the “Connected to xxxx” label below the battery and the app will disconnect/forget that device.
Method B.
Just go to menu (the three vertical dots in the top right side of the screen) -> Manage Devices.
Click on the red X circle to delete any of the Chargies you connected to in the past. Their name will go back to “chargie”, and you’ll be able to change it whenever you connect to them again.
5. Customize your Chargie’s name
For sure that if you have more than one Chargie, you’ll be needing this. The app knows its devices by their Address (the hexadecimal numbers below the name in the list), but it should also be easy for you to recognize them quickly. That’s why you can just tap “Rename” at the top of the screen and give it a new name. It’s that simple.
6. Yes, it’s in the icons
The three icons are very important to understanding Chargie. They’ve been designed to be intuitive, but just to keep things safe, this is their meaning:
Charging mode active
Lamp Mode Active, Switch On
Proximity Mode Active
All of their grey variants show the inactive status. Red bulb means Lamp Mode is active but switched on.
7. Download the Chargie App
You can download the Chargie app right from the standard Google Play on your phone by searching “Chargie”, or the link below:
