5,600,725 Members 37,835 Now Online
XDA Developers Android and Mobile Development Forum

Slow QI charging

Tip us?
 
skusa93
Old
#1  
Senior Member - OP
Thanks Meter 167
Posts: 312
Join Date: Aug 2007
Location: California
Default Slow QI charging

Ordered a QI charger off Amazon (the same Lerway Chinese brand one everyone seems to get) and it's charging incredibly slow. Not sure if the app I'm using to record the charge rate is incorrect or I'm not reading it correctly but it says it's charging at only +200mA max sometimes as slow as <50mA.

Anyone else experience this?

Current Phone: N5
OS: ParanoidAndroid
 
Znamir81
Old
#2  
Znamir81's Avatar
Member
Thanks Meter 19
Posts: 78
Join Date: Nov 2013
Quote:
Originally Posted by skusa93 View Post
Ordered a QI charger off Amazon (the same Lerway Chinese brand one everyone seems to get) and it's charging incredibly slow. Not sure if the app I'm using to record the charge rate is incorrect or I'm not reading it correctly but it says it's charging at only +200mA max sometimes as slow as <50mA.

Anyone else experience this?
What kind of power source you use to power the charger and what kind of cable do you use?
If you connect the charger to computer USB port it will not provide enough power for the charger. Same with cheap cables, like the ones mostly included with the generic QI chargers. You need a premium USB cable.
Also if you have a thick case on your phone it will diminish the charging current received by a coil in your phone.

Firstly check how much power and what current your charger gets, so instead of plugging the QI charger, plug your phone and check what amperage you get (I use Current Widget). If it's less then 1600mA (maximum amperage that N5 will allow from direct charging through cable) your charger is underpowered and you need to change socket charger to 2A one. If you're using 2A socket charger and still get under 1600mA then your micro USB cable isn't good enough.

Properly and fully powered Qi charger should charge your bare phone (without a case) at about 700-800mA.
 
skusa93
Old
#3  
Senior Member - OP
Thanks Meter 167
Posts: 312
Join Date: Aug 2007
Location: California
Quote:
Originally Posted by Znamir81 View Post
What kind of power source you use to power the charger and what kind of cable do you use?
If you connect the charger to computer USB port it will not provide enough power for the charger. Same with cheap cables, like the ones mostly included with the generic QI chargers. You need a premium USB cable.
Also if you have a thick case on your phone it will diminish the charging current received by a coil in your phone.

Firstly check how much power and what current your charger gets, so instead of plugging the QI charger, plug your phone and check what amperage you get (I use Current Widget). If it's less then 1600mA (maximum amperage that N5 will allow from direct charging through cable) your charger is underpowered and you need to change socket charger to 2A one. If you're using 2A socket charger and still get under 1600mA then your micro USB cable isn't good enough.

Properly and fully powered Qi charger should charge your bare phone (without a case) at about 700-800mA.
Thanks for the info I thought I was going crazy.

No case so that isn't an issue.

I have the phone connected direct to a 3A charger currently and am only getting 995mA charge rate with the screen on and it looks like full 1.5A with the screen off. Maybe a defective QI charger?

Current Phone: N5
OS: ParanoidAndroid
 
Znamir81
Old
#4  
Znamir81's Avatar
Member
Thanks Meter 19
Posts: 78
Join Date: Nov 2013
Nope. Everything is normal. You just need a better cable that will manage to transfer 2A of current.
QI charger needs 2A input to give 1A output on a coil. Giving about 70-80% efficiency rate, your phone would be getting about 700-800mA.
Since your charger gets only about 1A input it gives about 500mA output. Therefore giving that efficiency rate, your phone should be getting about 350-400mA tops. It is possible that your charger has lower efficiency rate (some have about 50-60%), so the values that you're getting are pretty normal unless you use a premium micro usb cable, preferably with thicker, like AWG24 or lower (the lower value the better) power wires.
 
t1.8matt
Old
#5  
Senior Member
Thanks Meter 388
Posts: 1,712
Join Date: Jan 2012
Location: Pittsburgh, PA.
Might want to try these cables, a lot of people have had great luck with using them on Qi chargers. Don't know which length you would need, they have 3 and 6 foot cables. For the price, I'm ordering 6 6ft cables.
http://www.monoprice.com/Product?c_i...seq=1&format=2
Google Nexus 5

Moto X DE

Nexus 7 1G
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes