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Accessories Rapid car charger for Epic?
- Thread starter TRSN
- Start date
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- samsung epic 4g
Rapid chargers will shorten the life of your battery, I'd stay away from them.
daddyd302
Android Enthusiast
Just turn off the phone while charging. When I need a quick charge and don't have all day to wait while in the car.
And what if important call comes in??
SirRicky85
Newbie
important calls will leave your a vm or text message if they can't get ahold of you.
That is a myth. the battery already has heat detection in it and will not over charge or charge too fast even if you have 2 amps available. Runnnig your battery down toi lower levels actually will more likely reduce a lithium batteries life.
here is the thing. Samsung has chargers with 1 amp for the same battery. The galaxy S appears to be .7 amps (700 ma.) That is almost certainly the result of a design in the wall wart to keep the physical profile low.
Use in the car is actully the most likely to be demanding on power since you are nav programs will be using GPS, full time screen, speaker phone, 3 or 4G data connections, and phone connection all concurrenlty. This can draw 400 to 500 milliamps or more. (take a full battery Epic and run all those at once without stopping and see if your 1500 mah battery lasts more than three or four hours) If you have a cheap car charger which can be from 200 to 500 amps you will either get very slow charge or battery drain even when "charging."
OP: On ebay find a reputable seller selling genuine Motorola car changers. they are 900 ma to 1 amp. You will not hurt your phone because it has built in the heat detection circuits (although don't run your kids game console though wifi with GPS and screen full time, that might get mighty hot!)
Thanks, nice to know. I'll have to check the car charger I bought from Sprint, and see what's it's output is. When you mentioned cheap chargers, you said 200 to 500 amps, I think you meant milliamps.
yes, miilamps 1 amp is 1000 ma.
What this means is if the phone is off and hooked to a oem .7 (700ma) charger, it will go from 0 battery to full 1500 in a bit over two hours. About 3 hours on a computer usb which is normally 500 ma.
But if the phone is one it can be itself pulling 50 ( a rough guess at standby under average Rf) to 600 ma (I bet wifi, GPS full time, 4g, full bright screen and blutooth might pull even more).
I've have had phones that will discharge on 500 ma usb connection while using wifi and 3g.
I use the 700ma sammy charger on my home desk, a 1 amp charger at my office, but have a generic cheap 300 ma charger in my bedroom since that is fine for overnight.
But for a car charger go with .9 to one amp if you are using your epic for nav. that way if you pop into your car at 25% and go for a half hour ride you will probably come out at 50%
the thing with ebay and motorola chargers is that there are a lot of very well concealed counterfiets, and you wouldst use a reputable dealer.
the good news is the investment in micro usb chargers is fairly efficient since chances are your next phone or any of your friends that need a charge will be micro usb as it is now widely a standard.
boomerbubba
Android Enthusiast
I use a Motorola-branded microUSB car charger, rated at 850 mA. It was pretty cheap on Amazon.
Recently I made a day-long driving trip and it performed well, keeping up with concurrent GPS use and streaming audio via Pandora for hours. I did start the trip with a full battery, but a lesser charger might not have been able to keep up with the load and there would have been a net discharge. I once had that problem with a cheap car charger for my old G1.
Recently I made a day-long driving trip and it performed well, keeping up with concurrent GPS use and streaming audio via Pandora for hours. I did start the trip with a full battery, but a lesser charger might not have been able to keep up with the load and there would have been a net discharge. I once had that problem with a cheap car charger for my old G1.
I used a cheap charger when I was using the GPS Navigation (which also keeps the screen on) and I went from 65% to 15% in about 45 minutes! As a result I got a 1 Amp charger and when I tested it, my charge actually started climbing while using the GPS for the same trip, it went from 40% to 60% in about the same time frame. I do the same method as Aero1, I have several chargers for both wall and car. I use my high output car charger in my car, a high output charger for work, a lower output one for home.
This is not quite correct. The battery asks for current from the charger instead of the charger forcing current to the battery. The charging current is not constant so the battery won't got fully charged in a bit over 2 hrs. That's also why a 1000mA charger won't hurt to your battery.
Just checked out my Samsung car charger, and I'm a little disappointed, it's only 700 ma. Will I be fighting a losing battle trying to use gps and charge with 700 ma.?
zetterwing
Newbie
Does anyone know a good resource to view the actual power ratings of all the available chargers? I would love to compare the available car chargers for my sweet new device knowing before hand that I needed a 1 amp push in the car. I was a sucker and short on time so I bought the one at Best Buy and I can't seem to find the output rating. Already threw the packaging away.
BTW the one I bought was 600mA.
BTW the one I bought was 600mA.
The output rating of the charger should be right on the device. I had to put the reading glasses on the read it though, super fine print.
zetterwing
Newbie
I thought that right after I posted. 600mA.
By the time I found out that my charger was under powered, it was past the 7 day return policy of the fake Sprint store where I purchased it. l didn't know at the time, but it wasn't an official corporate Sprint store, that offers a 30 day return policy. Be careful where you purchase your accessories.
No offense but I was completely correct. Not only is correct in theory, ti is correct in practie and I go from completely discharged to vompley charged in a little over two hourse with the 700 ma charger. It is 1.5 hours on my 1000 ma charger as well.
No where do I say the charger "forces" the current. What I am noting is how much amperage is available. From my tests, the Epic can in fact draw 1100 ma to share bewtween draw and charge.
The thing with nav is it isn't just gps. it is GPS, a failry constant 3 or 4 g data connection, fairly constant high processor use, screen on full time, speakerphone. I don't know if that pulls 300 or 500 ma. But if it is 400 ma that leaves 300 ma for charging. If you start with 25% (375 mah on the battery) and drive for an hour, 300 ma/h charging would give your 675 or aobut 45%.
So if you depend on one hour rides to add 50% to your battery get a 1000 ma. If you just want slightly more than than you started with 700 ma is probably sufficient. In any case be careful of generic cheapo car chargers which can easily be as low as 200 to 400 ma.
should be, but often not on car chargers.
Just joined the android community. Pretty sure i'm going broke, having bought 3 epics at the same time. I'll blame my daughter! 
Anyway, all sorts of power talk, i thought i'd pass on a great solution. I've been using this system for a while and it's great because you can charge just about anything..
Called iGo at iGo.com... they sell chargers/cables and then you buy tips for whatever device you have. They have a variety of options, including a Y adaptor which is great for multiple devices.
Their website doesn't mention power output, so i called and they said 'about 1a'..
So, it sounds like it'll be a good choice.. i've only had my epic for a week and haven't charged it in the car yet, so i can't say how fast it charges. I've had it hooked up and it does say it's charging.
I got mine at radio shack.. but im guessing you can get them in other places.
RocD
PS.. i have no connection to them, just saw the discussion and thought i'd throw my 2 cents in.
Anyway, all sorts of power talk, i thought i'd pass on a great solution. I've been using this system for a while and it's great because you can charge just about anything..
Called iGo at iGo.com... they sell chargers/cables and then you buy tips for whatever device you have. They have a variety of options, including a Y adaptor which is great for multiple devices.
Their website doesn't mention power output, so i called and they said 'about 1a'..
So, it sounds like it'll be a good choice.. i've only had my epic for a week and haven't charged it in the car yet, so i can't say how fast it charges. I've had it hooked up and it does say it's charging.
I got mine at radio shack.. but im guessing you can get them in other places.
RocD
PS.. i have no connection to them, just saw the discussion and thought i'd throw my 2 cents in.
How does the Epic tell the difference between a 1A-capable "USB" port and one that's merely 500mA-capable? I'm 99.9% sure that NO charger actually implements a faux USB hub to "properly" negotiate the power, and they all pull off shortcuts of some kind to detect "their" charger(*). I think HTC phones (or at least the Hero) put resistors between two of the pins to see whether they're pulled high, pulled low, or floating, and assumes it's a HTC high-current power supply if they aren't floating.
(*)cheap UPS'es pull off a similar trick with their fake USB ports to use its +5v line as a single-bit data port. The UPS monitor app on the PC watches the USB port to see whether or not something is connected and drawing power, and polls it occasionally to see whether it's sinking current or not. If it slowly alternates between high and low, the UPS is working normally. If it has a long high and short low, or short high and long low, the monitor app knows that the UPS is either providing battery backup or is about to shut down. Most people have no idea you can abuse USB ports and use them in ways mother nature never intended to convey information without actually implementing USB itself ;-)
(*)cheap UPS'es pull off a similar trick with their fake USB ports to use its +5v line as a single-bit data port. The UPS monitor app on the PC watches the USB port to see whether or not something is connected and drawing power, and polls it occasionally to see whether it's sinking current or not. If it slowly alternates between high and low, the UPS is working normally. If it has a long high and short low, or short high and long low, the monitor app knows that the UPS is either providing battery backup or is about to shut down. Most people have no idea you can abuse USB ports and use them in ways mother nature never intended to convey information without actually implementing USB itself ;-)
Does anybody make a low-profile cigarette lighter USB charging port that implements the official USB "charger" standard (shorting the two data pins together with a resistor not exceeding 200 ohms so the device can recognize it as a charger capable of delivering high current), or an adapter/cable that shorts the pins together? Or is hacking apart a cable still the only way to achieve it right now? I find it hard to believe that if chargers don't do it already, there's not at least one factory somewhere in China stamping out molded plastic plugs with metal inserts to pass through +5 and ground, and short D+ and D- together that just sits inline between the charger and cable.