Something you hear often these days: “My phone’s battery isn’t lasting as long as it used to,” or “I charged it all night and it’s already dead” or “It keeps hanging and I have to take out the battery”.
If you are having any battery issues with your phone, ask yourself: Are you using the charger that the phone’s manufacturer supplied in the box? Have you bought an “after-market” charger, bought off the shelf? Are you using a charger from another manufacturer to charge your phone? Did you buy one of those car chargers at the traffic light?
Since most phones these days have the same microUSB connector, people typically find any charger that fits and assume it ok.
However, what you might not know is that, not only could you be damaging your phone, but you could also be affecting the phone’s warranty.
The root of this issue is in the attempted standardisation by manufacturers to adopt the microUSB charger design as the charging port. The thinking behind this move was that, since you can make use of any charger, you will not throw your old charger away. You will therefore reduce e-waste, which is a win for the environment. However, while the physical design of the microUSB was adopted, the circuit paths inside the chargers are not universal.
In other words, the connectors are the same size but the chargers themselves are not the same. And just because the connector fits, it doesn’t mean that you should use any charger.
Four stages of battery charging
There are four stages that occur when you charge your phone:
Stage 1: As you connect your phone, the battery’s voltage quickly increases.
Stage 2: The voltage peaks and current from the charger begins to decrease.
Stage 3: The battery is fully charged and the charger cuts the current off from the cellphone completely.
Stage 4: Standby mode, where only a top-up charge is supplied when the battery drops below a specified voltage.
It is critical that your charger “understands” these stages and is able to adapt accordingly.
Here is what you need to look out for:
The wall-charger is built to take normal current and adapt the current to a level that your phone needs. If you look on the charger itself, you will see a tiny label that contains the input levels, for example: "Input: 100-240v~".
This means that, if you live in a country where the normal household voltage is between 100 and 240 volts and you put this charger in the wall, it will not blow up. However, take a charger from the US that is rated only at 110v and stick it in a wall socket in South Africa at 220v, and you will trip the circuit breaker and bye-bye charger.
Next you need to look for the output voltage. Most cellphone batteries fully charge to around 4.2 volts and so the charger output must be greater than 4.2v. If the charger is only rated to output 3v, then that will not charge a 4.2v battery.
Finally we need to look at the output amperage, this indicates the maximum amount of current available from the charger for the phone to pull what it needs. If the phone requires 700mA to charge and you happen to use a charger with a 1A output, the phone will draw only up to the 700mA.
However, where your phone requires 700mA and your charger only supplies 500mA, many issues can occur, ranging from very slow charges to overheating and complete device failure.
USB chargers and cables
USB charging is not immune either. It is very common to buy wall chargers that allow you to plug a USB cable into it to charge your phone. Equally common is to plug any USB cable into your laptop and let it charge your phone.
What you need to know is that there are currently three USB specifications: USB 1.0, USB 2.0 and USB 3.0 – and each one carries its own power specification. For example, in USB 2.0 it is 500mA, whereas in USB 3.0 it is 900mA and can go up to 1500mA.
You will find that the USB charger takes much longer to charge your device compared to a wall charger. The reason is a combination of the quality and thickness of the USB cable, the cable’s specification and the source of the charging.
Some laptops’ USB ports do not produce enough power to charge your device, which is why you see some Y-shaped cables so you can harness the power of both USB ports (common with external hard drives).
Quality of chargers
When you buy cheap chargers, it is not enough to look at the connector. Many cheap chargers don’t carry the worldwide CE, RHOS or MFI certifications that ensure the products are made lead free, work in mains plugs and in other devices as well as being from sustainable and established factories in the countries of manufacture. Devices that carry such approval usually mean that the products have clever circuitry that allows the devices to work well.
The cigarette-type-charger I bought from a “merchant” at the side of a busy road showed that my phone was charging as indicated by the lightning bolt inside the battery icon on the phone. However, when I opened up the charger, I found that the charger had poorly soldered wires, loose components and did not have a regulator.
This means that the charger could keep charging the phone even when it no longer needs to and it doesn’t protect the phone against power spikes and dips. Other chargers I tried simply fooled the phone into thinking it was charging and, even after a full hour of driving, the battery only increased by 2%.
I spoke to director of Wintec Solutions Rene Winter. He shares the dodgy-chargers concern and confirms: “Overcharge/discharge protection is critical. When connecting a battery or in-car charger to your phone, you can’t always be there to know when it’s full, so it’s important for a device to have circuitry that recognises when it’s full and automatically stops outputting power to the device.”
The USB charger cable that winds-up onto itself like dental floss does charge my phone at a very slow pace. However, while it is charging, the touch screen is non-responsive. Surely that can't be a good thing.
“Battery conditioning affects your phone and ‘shock charging’ phones – like plugging in when at your computer then leaving it there – affects the amount of charge cycles your phone’s battery has [reducing its life],” Winter said.
Even within the same cellphone company, different phones have different charging requirements, so don’t mix up chargers. They are made specifically to deal with the phone they were designed to charge. And certified to charge.