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Help Slow Charging mode

A

ajarnfalang

Well-Known Member
Every time you plug the phone into a computer or some 3rd party charger it says that it is "slow charging" because of the low current.

Is it bad for the battery to slow charge for long periods of time?

I'm guessing since modern batteries dont create a "memory" then it doesnt matter but i wanted to hear your thoughts.
 
It's the power rating of the charger. Big screen phones use a lot of juice and consequently have big batteries. To get these big batteries to charge in a reasonable time, the chargers are higher rated - i.e. run at a higher power.

For example, the charger for my Nexus 4 (also made by LG) is rated at 1.2 amps (I think), most 3rd party chargers, car chargers and USB connections are rated at 1 amp or less.

If the phone isn't being used, it will still charge though much more slowly. To speed this up a bit, you can turn the phone off.

If the phone is being used - particularly if the screen is on all the time like when using the GPS - then lower rated chargers may not be able to keep up and the battery level can continue to drop, though obviously, much more slowly than it would without any charger.
 
I get this also when I use my old charger for my S3. I used to use the block from my TF Prime before I sold it because it would output quite a bit more juice.
Wouldn't worry about it damaging the battery. You should be just fine with the lower output.
 
Ok. thanks. Because i have a blackberry charger at home that is 5v and i was wondering also if i could use it.

Since i dont think it will damage anything as long as it's micro usb it should be OK
 
Not sure if it's true on current battery technology anymore but I had always heard that, if any charging speed was potential damaging, faster charging was actually more stressful for a battery. I sometimes wonder if using the 2 amp charger from the original Nexus 7 on my Bionic's extended battery is why the extended battery now seems to hardly last more than the standard one. So no, I certainly wouldn't think slow charging could cause any harm, if anything, faster would induce more stress on the battery.
 
Verizon G2 is a very special phone, during we R&D the Battery Case of Verizon G2, I test many original USB cables and Chargers, we defined which condition will make Verizon G2 “slow charging” and “normal charging” and I want to share, actually no much theory on it:
If the Verizon G2 battery over around 70%, many 1A chargers or cables going to charge no “slow charging” will happen. Under 70%, many chargers or cables, plug-in will have “slow charging”, because the battery inside Verizon G2 is too dry. I think many G2 users have this experience too.
By my testing, here some cables and chargers combination will not happen “slow charging” even the battery inside is dry(0%):
Any 1.5A Brandname charger or over + Nokia CA-1010 cable
Any 1.5A Brandname charger or over + Nokia CA-179 cable(LONG CABLE)
Any 1.5A Brandname charger or over + SonyEricsson EC300 cable
Any 1.5A Brandname charger or over + BlackBerry Original short USB cable(0.3m)
Samsung ETA-U90UWE 2A Charger + it’s original cable
I hope my info can help any Verizon G2 users confusing about that
 
PowerBomb said:
...faster charging was actually more stressful for a battery...
Click to expand...

Yup. at least its true for lithium batteries (I dont know about other types)

Fast charging, overcharging, and over-draining all reduce battery lifespan. Thankfully phones have protection built in for overcharging and over draining.

@mugenpower: the cable, unless it is many feet long, should make an indistinguishable difference in charging capability. in future tests you can save time by just using one cable :)
 
I believe chargers supporting faster charging short pins together to signal the device higher rate charging is available, and the phone decides. I think cables that do this don't support data transfer. All things being equal, I don't think a properly designed cable is ever culprit...

I think if I found a cable that didn't support high rate charging it would get tossed aside as suspect because it wouldn't support data transfer. Maybe that mental model is defective. :smokingsomb:

Now it wouldn't surprise me if the phone throttled its charge rate based on its condition (temperature, charge level).
 
<<<<Happy engineer
Thanks for sending me on this adventure!

I didn't think this was possible because usb only has 4 wires and all of them are used...but I just looked up the pin diagrams for microusb and learned something new! microusb has an extra (5th) pin compared to standard usb. more searching suggests its for the usb OTG functionality.

What I'm finding online is that the phone watches the 2 data pins to see if they are shorted (or grounded...not sure which). If they are, then that is a signal to the phone that it can fast charge. If the data pins aren't shorted then the phone assumes it's connected to a current-sensitive device like a pc and only draws at the usb standard (500mA max for usb 2.0). Usually it is the charging device like the ac adapter, not the cable, that shorts the pins. That's why the stock cables work for both data transfer and for fast charging.
 
The above is interesting, though my LG wall charger only slow charges. My 2 amp 5 watt car charger is faster than any of the oem and non oem chargers I have. I need to)figure out something, waiting 3-4 hours for even a half charge is too long...sometime I don't get a full charge after 7 hours of charging.
 
Download battery monitor widget or something similar that will plot battery charging and discharging. The history will show you mA rate of charge but also battery temp. You can definitely see the charging current being accepted by the device.

Charge your phone using the non OEM charger you have... I presume it charges at a fast rate. I would run a test with my phone, but I can't p as it's being replaced. Hopefully I'll get that today. I could post some numbers later but maybe someone else would read this and do the experiment with their phone and charger.

For comparison, charge for a few more hours using your LG charger but with the cable from the non OEM charger if that is possible. It should charge at roughly the same rate.

You could have a bad cable, or a bad charger. This step may reveal if the cable is culprit.. if it charges at high rate, then your cable is bad. If it doesn't then your adapter is bad.

If someone else could post numbers, you could determine if the phone might be culprit.
 
FWIW: I just received my replacement phone. It's a VZW model. I used the included charger and cable but a Qi wireless charger: PowerBot PB1020 I purchased on Amazon. Phone went from 60% to 100% in 2hrs almost exactly... suggesting it would charge the battery from 0-100% in roughly 5 hours. I wish I could have provided mA consumption information but I think on Wireless charging mode, that would be misleading.

Next time I need to charge the device I will use just the microUSB port for comparison and report that information here.
 
You need a quality cable with at least 24 AWG power leads if going over 3'. Link depot has a very nice 6' 22 AWG power lead cable over at newegg. The phone can't compensate the voltage drop on cheap wires and well go into slow charge. It will not hurt it. USB, besides 3, is limited to 500mA, hence slow charge. It will pop if charging under 1A in most situations. There is a huge discussing over at xda about this.
 
As a follow-up, using my LG charger and cable direct to the microUSB connector, the phone charged from 79->100% in approximately 40minutes.

This is not so scientific. I got that measurement using the Battery Monitor Widget program against a new battery and phone where the estimation must still be rough. The utility was collecting samples every 10 minutes. Interestingly, the phone modulated the current draw, starting out with a max of 1588mA, dropping down to 1116, then 658, then 413mA, and once at 100%, 267 and 200mA for the next two 10minute intervals after that.

I suspect if I sampled more quickly and over a longer period of time, we'd see better what the charger and phone together is doing in real-time.

jastow: I cannot say how long then it will take to charge the phone fully, but until someone else does a better study, on the wireless charger, it takes mine an estimated 5hrs, and direct with the OEM charger and cable, approximately 3.33hrs.
 
It fluctuates the charge due to heat, use, percent of battery(trickles very low and near full), ect. The charging logic is pretty smart.
 
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