Can I Charge My Phone and Battery Pack Simultaneously with a Power Bank?

In summary, if you are charging the battery pack with 5V and the phone is connected, the phone will only be getting 0.1A. If you are charging the battery pack with 2.5V and the phone is connected, the phone will be getting the full 0.6A.
  • #1
Akmalidin
69
6
Hello,
I have built a portable power bank to charger my phone when necessary.
But I have a problem with it. When I charger the power bank, it is charging only my battery pack which is NiMh, it is not charging my phone at the same time.Therefore, I want to ask ,how I can make my system , so it charges my phone and battery when it is plugged to power supply.When the batteries in pack are full, they are charging my phone. So please let me know your opinions.The schematics is given in pic.
IMG_20160910_111657.jpg
 
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  • #2
Akmalidin said:
Hello,
I have built a portable power bank to charger my phone when necessary.

I see a problem in the middle section ... do you see it ?Dave
 
  • #3
Nope I don't see it. Could you be more specific?
 
  • #4
5V and 2.5V on the same line ??
 
  • #5
yes, the buck converter outputs 5v and it is connected to battery.Two battery gives out 2.5 volts.So when I measured the middle point, it showed 2.5v. What can we do about it?
 
  • #6
It looks to me like you are charging the NiMH batteries with 5V. I wouldn't...
 
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  • #7
Yes I am charging with 5v .Why would not you do that?
 
  • #8
Akmalidin said:
yes, the buck converter outputs 5v and it is connected to battery.Two battery gives out 2.5 volts.So when I measured the middle point, it showed 2.5v. What can we do about it?

you shouldn't have 5V and 2.5V coming together at that point

Akmalidin said:
Yes I am charging with 5v .Why would not you do that?

cuz you are likely to cook them
there should be a separate line to a correct charger circuit for the NiMH's. The NiMH output voltage total should be 5V and then a separate switching circuit to switch between the 1st 5V supply and the battery pack before going to the phone the second 2.5 to 5V converter isn't needed
 
Last edited:
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  • #9
What if I lower the 5v to 2.5v as the battery pack voltage and step it up to 5 v?
 
  • #10
Akmalidin said:
What if I lower the 5v to 2.5v as the battery pack voltage and step it up to 5 v?

that's a bit pointless because as I said in my last post you don't need the second converter, just a waste of space and resources
increase your battery pack capacity to 5V is a much wiser move. I really don't see the point of a 2.5V battery pack
 
  • #11
Read up on the charging requirements for NiMH cells before going any further.

You aren't really meant to charge them from a constant voltage source. They should really be charged by a constant current source. Any kind of medium/fast charging also needs charge control (eg circuits to stop over charging when the battery is full). Overcharging a NiMH cell can sometimes cause them to overheat. That can cause the heat shrink insulation around the cell to split leading to short circuits and fire. Been there, done that.

Sometimes it's easier, cheaper and safer to just to buy one.
 
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  • #12
The way its wired now the buck converter is probably pushing too much current into the NiMH pack causing an overload. The buck converter goes into current limiting mode and that's why voltage drops to 2.5V. So you're using the boost converter because the buck converter is overloaded. That's a crazy thing to do. There should be a charging circuit on the 12V line for the NiMH pack and only the buck converter to power the phone.
 
  • #13
https://e.mail.ru/attachment/14741015700000000579/0;1 I added couple of batteries to make battery pack 4.8 v. But still it is not charging my phone. I even tried to charge my phone from a buck converter which outputs 5 v and connected to power supply. My phone was only getting 0.1A .But when I connect only battery pack it was sucking 0.6A .Why phone is taking only 0.1 A?
 
Last edited:
  • #14
This is the way I connected my phone and buck converter. Still cannot understand, why my phone is taking only 0.1 A.Please let me know your feedback.
IMG_20160917_113911.jpg
 
  • #16

What is a power bank phone charger?

A power bank phone charger is a portable device that is used to charge a mobile phone's battery when there is no access to a traditional power source, such as an electrical outlet. It typically has a built-in battery and can be charged beforehand, allowing it to store energy and then transfer it to a phone when needed.

How does a power bank phone charger work?

A power bank phone charger works by storing electrical energy in its internal battery when it is connected to a power source, such as a computer or wall outlet. When a phone is connected to the power bank, the stored energy is transferred to the phone's battery, charging it.

How do I choose the right power bank phone charger for my phone?

In order to choose the right power bank phone charger for your phone, you should consider the capacity and output of the power bank. The capacity is measured in mAh (milliampere-hours) and should be equal to or higher than your phone's battery capacity. The output should match or exceed your phone's input voltage and amperage. It is also important to consider the size and weight of the power bank for portability.

How long does it take to charge a phone with a power bank phone charger?

The time it takes to charge a phone with a power bank phone charger depends on the capacity and output of the power bank, as well as the phone's battery capacity. Generally, it can take anywhere from 1-3 hours to fully charge a phone with a power bank.

Is it safe to use a power bank phone charger?

Yes, it is safe to use a power bank phone charger as long as it is used properly and purchased from a reputable brand. It is important to follow the manufacturer's instructions and avoid overcharging the power bank or exposing it to extreme temperatures. Additionally, make sure to only use a power bank that is compatible with your phone to avoid any potential damage.

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