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Problems charging on 12V (car) chargers

G

garybeck

Android Enthusiast
I have a bunch of the little "stubby" chargers that go into a 12V car outlet and provide one or two USB charger outlets. They look like this:

$(KGrHqN,!pME9o+dPjG8BPdEBCRZ8g~~60_1.JPG


I've been noticing a problem. When I plug in through these adapters, often the device says it's connected and charging, but the battery state of charge doesn't actually go up. In fact it often continues to discharge as I use the device.

At first I just thought I had a bad cord or a bad adapter, but now it seems this is happening with a bunch of them.

Am I the only person that experiences this? Did I just make a mistake buying cheapo adapters on ebay? Are these adapters limited in the amperage they can deliver? I'm thinking when they get connected, the device senses voltage and says it's charging but there's not enough amperage to actually provide a charge. Also, the ones that have two USB outlets in a single adapter... are they more problematic because they have less amperage in each outlet?

I have found the problem with a variety of devices... my LG Optimus V, my kids' Galaxy Tabs, and my friend's Iphone. Just basically very inconsistent reliablity with these adapters and the main symptom is it says it's connected and charging, but the device actually continues to discharge.

Any help would be appreciated. I could tear my hair out testing every one of these I have but it would help to know if others have similar experiences and what could be the cause.

thanks
gary in vermont
 
A car charger doesn't put out as much power as a wall charger. The short answer is, you're using more power than it is providing. If you let it sit, you will notice it IS charging, just significantly slower than you are used to.
 
ExtremeNerd said:
A car charger doesn't put out as much power as a wall charger. The short answer is, you're using more power than it is providing. If you let it sit, you will notice it IS charging, just significantly slower than you are used to.
Click to expand...

OK if that's the case it would also follow that:

1) some car chargers provide more power than others and if I should be able to find one that can charge my devices adequately while I'm using them at the same time and perhaps the ones I have are particularly whimpy.

2) it would be really useful to know the amperage of the charger before you buy so you can compare between models and find the higher amperage ones.

correct?
if so, what's considered high amperage? for example, what would I get out of an AC charger or plugged in to a computer (I never have trouble with either of those).

thanks
 
One thing you need to be aware of is that anytime there is more than one outlet coming out of a single source you have a chance that the power is split between all available outlets - despite usage.

So in this case, 2.1a can be split to 1a to both outlets simultaneously regardless. So, only one device being plugged in will still receive only 1a. And two would each receive 1a.

Some are smart enough to carry all power to one when the other is not in use. Like a router.

You may be best off getting an adapter that has a single output. Or if you need a dual, find one that is (usually clearly marked) able to provide all power to one socket, but will split the power if both are in use.
 
gtbarry said:
One thing you need to be aware of is that anytime there is more than one outlet coming out of a single source you have a chance that the power is split between all available outlets - despite usage.

So in this case, 2.1a can be split to 1a to both outlets simultaneously regardless. So, only one device being plugged in will still receive only 1a. And two would each receive 1a.

Some are smart enough to carry all power to one when the other is not in use. Like a router.

You may be best off getting an adapter that has a single output. Or if you need a dual, find one that is (usually clearly marked) able to provide all power to one socket, but will split the power if both are in use.
Click to expand...

yeah I agree. I would add, there's nothing about the 12V outlet in the car itself that limits the charge current. At most there is a fuse inline that will blow if there's a short or overcurrent, but that will not be a factor here. It's all about the adapter. The adapter has a maximum amperage. It could be for the total of the two USB outlets, or there could be two separate independent charging circuits inside the adapter.

my "beef" with the ones I have at least, is that the output is undersized. Regardless of whether they are separate circuits or just in parallel, the device should be designed to actually CHARGE when it's connected to a device. Otherwise the thing is completely useless. I realize every device has a different power consumption but my little LG optimus phone is should be able to operate and charge at the same time, and if not it's a complete waste of money. Buyer beware I guess, and try to look at the amperage output of the charger.

bottom line is, you can't just buy the cheapest 12V adapters you can find and assume they're going to do the job and charge your device effectively.
 
Hello Gary,

I am having the exact same issue as you have described here. When I plug any device into the 12V charger in my vehicle, it notices and shows that the power is connected but none of my devices charge, rather they slowly depreciate in power.

I noticed you posted the problem a while ago. I'm hoping that you have resolved your issue, and was wondering whether you'd share the outcome.

I honestly can't figure out what is happening? I've tried various chords, converters, and multiple phones and even as iPad that notices the power supply but says, not charging.

Thank you!



garybeck said:
I have a bunch of the little "stubby" chargers that go into a 12V car outlet and provide one or two USB charger outlets. They look like this:

$(KGrHqN,!pME9o+dPjG8BPdEBCRZ8g~~60_1.JPG


I've been noticing a problem. When I plug in through these adapters, often the device says it's connected and charging, but the battery state of charge doesn't actually go up. In fact it often continues to discharge as I use the device.

At first I just thought I had a bad cord or a bad adapter, but now it seems this is happening with a bunch of them.

Am I the only person that experiences this? Did I just make a mistake buying cheapo adapters on ebay? Are these adapters limited in the amperage they can deliver? I'm thinking when they get connected, the device senses voltage and says it's charging but there's not enough amperage to actually provide a charge. Also, the ones that have two USB outlets in a single adapter... are they more problematic because they have less amperage in each outlet?

I have found the problem with a variety of devices... my LG Optimus V, my kids' Galaxy Tabs, and my friend's Iphone. Just basically very inconsistent reliablity with these adapters and the main symptom is it says it's connected and charging, but the device actually continues to discharge.

Any help would be appreciated. I could tear my hair out testing every one of these I have but it would help to know if others have similar experiences and what could be the cause.

thanks
gary in vermont
Click to expand...
 
Hello!

Mine is only a charger with one USB port, but I'm having these same problems. Did your problems resolve with the purchase of a new, better quality converter?
 
Hi

Yes, you need to get car chargers with higher outputs. You can get 2 amp ones. These are good for most devices. The problem is that in the car you are often using both mobile data and gps at the same time. These are both high power users.

Roger
 
Screenshot_2014-11-22-19-56-58_red_x_on_battery_icon_but_itS_charging.png




on a flagship (i.e., Galaxy Note 3, LG G3) these things won't work. the battery will continue to discharge albeit slowly yet show a 'charging' notification. sometimes, they won't charge at all, and on a Samsung will show a 'red X' on the battery symbol or a LG will display a 'for safety, charging via this unsupported accessory has been disabled'. in both instances the phone is disabling charging because it thinks the lower output might actually damage the device or battery.



On budget, cheap phones (LG Lucid 3, ZTE Merit, Samsung Galaxy Precedent, etc) they will charge fine, sometimes faster than you'd expect. but that's because not only is the hardware lower spec and less demanding on the battery, but the battery is often an undersized, low-rated battery and doesn't have monster demands.

It does suck for those who want a smartphone and the convenience of charging via your vehicle. the only workaround i know of is using a power inverter that turs 12V DC to 110V AC. but you want to have the engine running if you use those, as they will drain the car battery super quick! if the low battery alarm goes off on a power inverter often your car will refuse to start (mine did, but it was a 1984 Chrysler with one of those reduction starters that took tons of amps to crank. but i'm not willing to test it on my modern Saturn)
 
Keep in mind that it is also dependent on the type of cable you're using to charge as well. I've tried off-brand cables in my car, and my battery will drop or hold steady at whatever the percentage was when I plugged in. When I used cables I purchased from Monoprice, it will actually charge my phone during heavy use (using Waze, playing Ingress, streaming music via bluetooth with Play Music). I have a 4.2 amp converter and I use a 3 foot cable, and haven't had any issues.
 
It's crucial to use a charging adapter that (a) outputs sufficient amperage for the device(s) and (b) correctly identifies itself to connected devices. If a smartphone believes it's connected to a standard USB port then it will only draw 500mA regardless of the charger's capability.

My own car charger outputs 2.1A, and tells my phone that it's "AC charging" so that it draws the same 1.5A as provided by its wall charger at home.
 
It's like that with my phone, there's a specific manufacturer's car charger for it. plugs in the cigar outlet, otherwise it only draws 500mA on anything else.
 
If using hotspot mode it won't charge either. tried that once. was trying to get internet on my tablet while on the go and even plugged in, my Note 3 acting as a wifi died pretty much like it would if not plugged in at all. it had the 'red X' as well. that 'red X' would go away if disabling hotspot mode, but still didn't charge. just drained less quickly.

I have not yet found a car charger that will charge a flagship. tried the cheap $5 to even the expensive $49 chargers with MicroUSB and none will output enough for a flagship.
 
I failed to mention that I'm using a Galaxy Note 4, I only use the charging cable that came with my phone at home when I'm charging at night. Which cables are you guys using when charging in the car?
 
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