Suggestions For A Power Bank

[amit.tiger12]

My N4's official charger was of 1.2A...... I expected charging at speed of my charger from 2A port, but it can't ..... Yeah i know using phone while charging is not recommended, but i do it sometimes

I also play on nexus 5 while charging

 

[sksundram]

I signed up for OnePlus 10k mAh power bank. I will buy it as soon as it's launched. I hope it's under Rs 1k.
It's high time I get a power bank for myself. Thanks for the information sksundram.

Sadly, It will cost INR 1399. It was available for INR 997 for a brief period on Amazon before the initial launch. I missed it. Well, I am gonna buy it for sure but many users have shown their frustration on OPO forum for the hiked price.

Here's the forum link: *forums.oneplus.net/threads/week-23...launch-date-blogger-meet-in-bangalore.309585/

And by 'signed up', you mean to 'sign up to be notified through email when it becomes available'. Right?

Update: The sale is on. Buy soon.

 

[andy_65_in]

been using MI 10000 MaH powerbank from flipkart-its good-does what it says

 

[sksundram]

^ OP needs a powerbank to charge two devices at a time.

 

[amit.tiger12]

^ Xiaomi 16,000mAh Mi Power Bank

charge 2 device simultaneously at 2A

 

[bssunilreddy]

^ Xiaomi 16,000mAh Mi Power Bank

charge 2 device simultaneously at 2A

+1 to this.

Link:Online Shopping India, Search and Buy Product Deals for Cheap Price. Open Shops Online for Free

 

[sksundram]

^ Xiaomi 16,000mAh Mi Power Bank

charge 2 device simultaneously at 2A

Yeah, but it costs 1800+ on ebay.

+1 to this.

Link:Online Shopping India, Search and Buy Product Deals for Cheap Price. Open Shops Online for Free

It definitely looks fake.

 

[amit.tiger12]

OnePlus 10000 mAh Power Bank: Amazon.in: Electronics

 

[$hadow]

When charging two device ti will be providing 1A not 2A.

 

[amit.tiger12]

When charging two device ti will be providing 1A not 2A.

what is "ti"???

 

[Vyom]

what is "ti"???

A typo.

Btw,
Seriously PnePlus Powerbank : Rs 1399... what a silly way to make money. That price is the reason, why isn't out of sale even now.
I will wait for price to come down, if it ever will. Or some offers. Doesn't deserve more than 1k. :/

 

[sksundram]

^ The pricing of OPO powerbank has got insane amount of flak on Amazon as well as OPO forum.

 

[jackal_79]

Hi i found this review in amazon site.

Amazon.in: Sumesh's review of ADATA PT100 10000mAH Power Bank (Black-Green)

Can someone explain this?

 

[icebags]

Hi i found this review in amazon site.

Amazon.in: Sumesh's review of ADATA PT100 10000mAH Power Bank (Black-Green)

Can someone explain this?

mAh rating on any power bank - its just the rating of the batter it uses inside, which is/are 3.7v lithium ion cells normally.

so, to charge a fone through usb, it has to make 5v out of 3.7v of the lithiums.

a 1000mah 3.7 means 1Ax3.7V=3.7 watt hour

if we conver this 3.7watts to 5v ratings, then it would mean 3.7W/5A=740mAh (considering no power loss, i.e. 100% efficiency)

this means then the 3.7V lithium battery supplying 1000mA, the bank is outputting 740mA @ 5V

and no converter is 100% efficient, so u get may be 80-90% of the 740mA.


this will again get converted to 3.7V inside fone, say another 10-20% loss. so, if the power bank is good, u may expect a 1,000mAh powerbank to just charge a 700mAh batter fully once only, due to all the conversion loss.

similarly, a 10,000mAh powerbank basically means a 7,000mAh from the view of a fone battery.

 

[Faun]

Output ampere 2.1A

Charges fast.

 

[$hadow]

what is "ti"???

Sorry I was typing ''it''

 

[jackal_79]

mAh rating on any power bank - its just the rating of the batter it uses inside, which is/are 3.7v lithium ion cells normally.

so, to charge a fone through usb, it has to make 5v out of 3.7v of the lithiums.

a 1000mah 3.7 means 1Ax3.7V=3.7 watt hour

if we conver this 3.7watts to 5v ratings, then it would mean 3.7W/5A=740mAh (considering no power loss, i.e. 100% efficiency)

this means then the 3.7V lithium battery supplying 1000mA, the bank is outputting 740mA @ 5V

and no converter is 100% efficient, so u get may be 80-90% of the 740mA.


this will again get converted to 3.7V inside fone, say another 10-20% loss. so, if the power bank is good, u may expect a 1,000mAh powerbank to just charge a 700mAh batter fully once only, due to all the conversion loss.

similarly, a 10,000mAh powerbank basically means a 7,000mAh from the view of a fone battery.

What is 0.74 in my mentioned calculation ?. Agreed that nothing would be 100% efficient. So is there any way to calculate the efficiency?

 

[icebags]

What is 0.74 in my mentioned calculation ?. Agreed that nothing would be 100% efficient. So is there any way to calculate the efficiency?

0.74 is the voltage conversion ratio = 3.7v/5v

lithium battery outputs 3.7v, but fone usb sockets require ~5v source.

about the measurement, u can see this video, measurements start @ 3:30, but u should watch it from beginning. the guy describes it well, but if u still get any doubt, u may ask.

[YOUTUBE]pxNLTRl36HQ[/YOUTUBE]