Power banks or portable chargers are one of the most convenient ways to power your portable devices when you don’t have access to a power outlet.
Running out of power can sometimes bring a lot of troubles and even ruin your vacation or business trip. It is important to make sure your portable charger is fully charged, so you can avoid any unpleasant situations.
How Do You Know When Your Portable Charger Is Fully Charged?
Portable chargers, also known as power banks, come with a number of tiny LED lights that indicate their states before, during and after charging. Knowing these states is crucial if you want to use your unit as safely and effectively as possible.
LED Lights and How They Work
4 Indicator LEDs
In many power banks, you will find 4 tiny blue LED lights. One of these will blink once the unit is plugged into a power outlet. This shows you that the device is now charging.
While connected, the first blinking light indicates that the power bank is charged up to 25%; the second, up to 50%; the third, up to 75%; and the fourth, up to 100%. When all four lights are lit without blinking, that means the unit is already fully charged and must be removed from the power source right away.
When disconnected from a power source, all LEDs on your portable charger will be unlit. However, you can still determine how much power it currently holds by clicking the Check button (usually found on the side).
Four steady lights mean your power bank is still fully charged; 3 indicates a minimum charge of 50%; 2 means it is at least 25% charged, and 1 light means the charger has 5% power left. If all the lights remain unlit even after pressing the Check button, that means your unit is completely discharged.
If you find all 4 LEDs blinking, it is a sign that the device is has developed some fault and must be checked by a technician or, if the warranty still applies, the manufacturer.
2 Indicator LEDs
In some cases, power banks will have only two LED indicator lights – usually, a blue LED and a red LED. If you connect a mobile device to your power bank and get a steady blue light, that means the device is charging.
No Indicator LEDs
Cheap power banks usually come without LED indicators. Instead, you have to read the manual and find out how long you need to charge your unit. In this case, you’ll need to do your own math. Start by determining your power bank’s charging capacity in mAh (milliampere-hours) and the current delivered from the power source in A (amperes).
Let’s say your unit has a capacity of 10000mAh, h refers to hours, and the current delivered is equivalent to 2 Amperes. First, divide 10000 mAh by 1000 (1Ampere = 1000 mAh) to convert mAh to A, then divide the quotient by 2A. The final answer is 5h, which means the maximum charging time for your power bank is 5 hours.
Unfortunately, some power bank manufacturers exaggerate their products’ holding capacity. This means the above method may not always be accurate. In that case, you can supplement it with good old-fashioned common sense while keeping two things in mind: first, your power bank will hold less power over time. Second, this decrease will go faster when you constantly subject your unit to high temperatures. For example, it will drain faster when you let it bake in your car on a hot day.
In any case, you are likely to see a difference after the first 100 to 500 charge/discharge cycles. Of course, this will depend on the quality of your power bank, but 500 charge cycles can usually reduce holding capacity by 20%. Lower-quality units may not even reach 100 cycles.
When LED Indicators Aren’t Working
When your unit’s LED indicators are busted, you can simply test it to know if it’s working or not. Plug it in for a short charge and try charging a mobile device on it. If your device is charging from your power bank, then your power bank is obviously fine. Otherwise, you can measure the batteries’ terminal voltage using a voltmeter. Most power banks run on 18650 type lithium-ion batteries, which should have a terminal voltage of 4.2 volts at maximum charge.
How to Make Sure Your Power Bank Charges Properly
There are many things that affect your power bank’s ability to charge properly. For starters, it has to charge only with the manufacturer-provided cables, or it may never reach its full charging capacity. Generic chargers won’t only reduce charging speed but also create potential issues with charge retention.
Also, charge your portable charger only when the battery is low, or it will start charging slower with time. But be sure not to overcharge it either as this can cause your battery to overheat, swell, and result in irreversible damage not only to itself but on all connected devices as well. Even if your charger continues to work, its lifespan will decline faster than intended.
Finally, make it a point to use your unit at least once a month to keep it from discharging beyond the critical level, which is another potential cause of permanent damage.
Choosing a Portable Charger
The bigger your battery’s capacity, the longer it takes to charge it fully, so consider this when buying a portable charger. If you plan to use it for your day-to-day commute, get a smaller power bank so you can charge it up quickly. If capacity is more of an issue than charging time, then get a bigger power bank.
At the end of the day, knowing when your portable charger is fully charged and how long it takes to get there is crucial to its function and longevity. To stay on the safe side, don’t hesitate to invest in a high-quality power bank that will last long, even if it costs a little more.
There are cheaper alternatives, but you won’t be saving money nor time if they’re always broken and needing to be replaced. Spend time researching good brands and don’t forget to consider how often you use the device when you deciding which power bank to purchase.