Warning: Not all Cell phone chargers are the same and are not interchangeable

Are all chargers the same ? NO

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 is already dead” or “my phone 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 ? Are you using the charger from another manufacturer to charge your phone even though it is not the same company ? Did you buy one of those car charger at the traffic light ?

Since most phones these days have the same micoUSB connector people typically  find any charger that fits and assumes it is ok.

However, what you might not know is that not only could you be damaging your phone but you could be doing such serious damage that it voids the phone’s warrantee !

The root of this issue is in the attempted standardization 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 therefore reduce e-waste which is a win for the environment. However, whilst 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. Therefore, just because the connector fits, it doesn’t mean that you should use any charger.

The 4 stages of Battery Charing:

There are 4 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: When the battery is fully charged and the charger cuts the current off from the cell phone 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:

Wall charger with correct specification

The wall-charger is built to take normal current and bring it down 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. Usually something like 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 wont blow up. However take a charger from the USA 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 cell phone batteries fully charge to around 4.2volts and so the charger output must be greater than 4.2. If the charger is only rated to output 3.0v 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 – no problem here. However where your phone requires 700mA and your charger only supplies 500mA is when many issues can occur ranging from very slow charges, to overheating, to complete device failure.

USB Chargers and cables:USB Chargers for wall and car

USB charging is not immune to issues too. 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 simply plug any USB cable into your laptop and let it charge your phone. What you need to know is that there are currently 3 USB specifications: USB 1.0 , USB 2.0 and USB 3.0 – it seems like each one carries it’s own power specification. For example in USB 2.0 is 500mA whereas in USB 3.0 it is 900mA and can go up to 1500mA.  You will note that the USB charger take much longer to charge your device compared to a wall charger and the reason for it 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 do not produce enough juice 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:

Chargers with various heads

When you buy cheap chargers it is not enough to look at the connector.  Many cheap chargers don’t carry, CE, RHOS, MFI approvals. These are important worldwide certifications that ensure the products are made lead free, work in mains plugs and in other devices as well as sustainable and established factories in the countries of manufacture. Devices that carry such approval usually mean that the products have clever circuitry that allow the devices to work well.

The cigarette-type-charger I bought from a “merchant” by the side of a busy road showed that my phone is charging as indicated by the lightning bolt inside the batter icon on the phone. However when I opened up this chargers I noticed that the charger has poorly soldered wires, loose components and did not have a regulator which means that the charger could keep charging the phone even when it no longer needs to and it also doesn’t protect the phone against 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 Rene Winter who is not just the Director Wintec Solutions but also has this impressive qualification Beng (hons) Mechatronic Engineering and he shares the Dodgy-Chargers-Concern and confirms that “Over Charge / 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 is full, so it’s important for a device to have circuitry that recognises when it is 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 whilst it is charging the touch screen is non responsive. Surely that cant be a good thing…

Rene adds that “Battery conditioning affects your phone and “shock charging” phones – like plugging in when at your PC then leaving affects the amount of charge cycles your phones battery has (reducing its life ) Although many new phones and Lithium Polymer themselves it is important to look for a Lithium Polymer charger as they do not have the memory set like other batteries which effectively means longer life for your devices and better conditioning.”

Even within the same cell phone company, different phones have different charging requirements so don’t mix up chargers. They are designed specifically to deal with the phone they were designed to charged. And CERTIFIED to charge.

Solar Chargers

Powertraveller Solar Charger

Solar charging is the most under utilised technologies in Africa. However this is largely due to cheap versions that don’t work and have damaged or ruined the term “solar charging”. Ever tried those solar powered garden lights ?

There are many types of panels and technologies that go together to make a Solar Charger and unfortunately the materials and techniques that work well are not cheap, hence you normally have to pay for a solution that works – but you will see the rewards !

Products Like Powertraveller award winning range use glass bonded panels that actually collect UV and maximise the efficiency of how it coverts this UV to electricity – making them extremely efficient, robust and temperature tolerant (-20 – +40 degrees ! )

Technologies like MPPT – Powertravellers patented Maximum Power Point Technology means there panels can harness and store (in batteries) the charge so when it gets over cast, it still outputs a regulated current (not AC – damaging to devices ) and therefore allows maximum output and power efficiently to your device.

So in summary:

1. Stick to only using the charger and the USB cable that came with your phone.

2. If you don’t have your charger with you, look carefully at the available charger you are about to use and make sure the power matches what your phone needs (see above)

3. Carry your own USB cord that came with your phone. Its designed and built specifically to deal with your phone.

4.  Whilst it is temping to buy the cheap-no-name-brand-aftermarket-chargers you are literally risking the life of your phone and your battery. There is a reason that an official-charger costs more than a cheap import.

5. If you buy a non-official charger, look on the packaging to make sure it is certified for the phones you want to charge.

25 Comments

    • should be perfectly fine. In SA we use 220v so your charger can handle it. To be safe, switch off the wall plug, plug in the charger without it being connected to anything and switch on the wall plug. Assuming the house didn’t trip you are good to go

  1. So can I use an original Samsung phone USB cable or my original Asus cable (which I use for my Nexus 7) for my Huawei phone? I use the original Huawei plug/charger that came with my Huawei Y300. Would using either these USB cables make any difference?
    The reason being, is that the usb cable that came with my Huwaei phone is loose and doesn’t charge the phone.
    Thanks!

  2. Hi my USB cable that comes with a adapter for charging nexus 4 phone is damaged, can I user USB cable of black berry phone and connect it to my adapter(nexus 4) to charge nexus 4? Is it safe bcoz original charger is unavailable

    • Yes. As long as you using original charges and not some cheap ones from the local market then you should be ok. Try not to have them right next to your head as you sleep just in case…

      • I’m using the original chrger for my phone but my friends also comes n chrge dere fone with my charger.. Will it affect my charger or fone.. Last tym i hvng little problem with my fone battry.. I ws chrging it bt aftr few min the chrging indication of the battery ws not shown bt the light for charging was stil dere.. Can u tel me d reason y its happening lyk dis

  3. hi, i have a samsung pocket and i used a car charger and now it wont turn on, i never checked the specs of the charger but its one of those you buy off the street corner. when i use my normal charger, instead of charging its turning its self on and before the startup is complete its turning off again. i hope i havent messed uo my charging system as this was my “ol’ faithful”. or maybe i need a new battery??

  4. My phone has started not charging on the wall charger it’s a Samsung s3 it says it’s charging but takes ages and when I unplug it the battery percentage drops but it will charge fine off a portable power bank??can u help

  5. Wow. I’m notorious cor losing/misplacing my chargers and fit into that category with the mindset that, “one android charger and cord fits all.” However, My LG cellphone has proved me wrong. Nothing would charge this phone beyond a 7% charge. My last hope was buying a Juicy Power charging station (which fortunately worked).
    Your article tells me why this did the job. I’m sharing it with everyone (especially my electrical/computer engineer husband). Thank you.

  6. That was really helpful. But help me out here. I lost my htc one e8 charger and i dont know my phones specifications. So how can i buy a new one? Also are the chargers marketed as oem original? Can i trust?

  7. Aren’t the charging circuits on the phone, (or even battery itself)? So all the charger needs to do is provide voltage and any reasonable current? I’m not sure if chargers really need to increase/decrease current etc.

  8. So I have an old Nokia 3310, and want to charge it on a USB charger. I can get a USB to Nokia DC3.5mm adaptor, so should I be good to go because the battery voltage and amperage is less than what my USB charger states for those values?

3 Trackbacks / Pingbacks

  1. Tech of the Week: my interview on SAfm Radio | The Techie Guy - Liron Segev
  2. Techie Abroad: Keeping your devices powered whilst travelling is a real challenge | TheTechieGuy
  3. Cell Phone Chargers Interchangeable | You Get Cell Phone Deal

Add your comment