I'm having issues finding an off the shelf pcb that can do what I want.
I have a battery powered system that I want to charge without interrupting power like laptops do. I am currently using an over-sized 5vdc buck converter.
Does anyone have any experience with such things? My battery is about 6AH and would prefer at least 1 A of charge current.
Using a system while charging it's battery
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- adafruit_support_mike
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Re: Using a system while charging it's battery
Our LiPo chargers do exactly that: http://www.adafruit.com/products/280
Most of the magic lives in the MCP73861 at the heart of the circuit. That does all the level checking, current routing, etc.
Most of the magic lives in the MCP73861 at the heart of the circuit. That does all the level checking, current routing, etc.
- chisleu
- Posts: 18
- Joined: Sun May 26, 2013 9:41 am
Re: Using a system while charging it's battery
THANKS!
EDIT: It does allow for a switchable charge/run mode, but I'm looking for a laptop style plug in for power + charge circuit.
EDIT: It does allow for a switchable charge/run mode, but I'm looking for a laptop style plug in for power + charge circuit.
- adafruit_support_bill
- Posts: 88154
- Joined: Sat Feb 07, 2009 10:11 am
Re: Using a system while charging it's battery
Can you be more specific? Are you looking for something with a USB port?but I'm looking for a laptop style plug in for power + charge circuit.
- chisleu
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- Joined: Sun May 26, 2013 9:41 am
Re: Using a system while charging it's battery
I'm sorry. I mean an uninterrupted power supply and charging circuit.adafruit_support_bill wrote:Can you be more specific? Are you looking for something with a USB port?but I'm looking for a laptop style plug in for power + charge circuit.
So I can boot my system and use it on battery, and when the battery runs low I just plug in 1 plug which starts powering the system and then the batteries automatically switch from drain to charge. Much in the way a laptop behaves.
I figured there would be something off the shelf that could do it, given how many cell phones/laptops/etc do it.
- adafruit_support_bill
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Re: Using a system while charging it's battery
All of our chargers do that. You can charge the battery and power a load at the same time.
The SolarLiPo charger ( http://www.adafruit.com/products/390 ) has a more sophisticated load-sharing scheme than the others. It can provide full power to the load while still regulating the charge current to the battery.
The SolarLiPo charger ( http://www.adafruit.com/products/390 ) has a more sophisticated load-sharing scheme than the others. It can provide full power to the load while still regulating the charge current to the battery.
- chisleu
- Posts: 18
- Joined: Sun May 26, 2013 9:41 am
Re: Using a system while charging it's battery
Very nice. Then I am very confused. I'm very happy to purchase 1 solar panel and 1-2 chargers but I don't have room for two solar panels on my little project. I like the word very.
Can I setup these batteries as 2x 2P and connect them to this board: http://www.adafruit.com/products/390 ....
Then put the load sides of the two charger PCBs in series to make my 7.4V for my project?
Here is my project thus far with a temporary / hard wired battery for testing. I still need to add a 3d printed panel with mHDMI and mUSB female connectors and the power input for the charger circuits.
Can I setup these batteries as 2x 2P and connect them to this board: http://www.adafruit.com/products/390 ....
Then put the load sides of the two charger PCBs in series to make my 7.4V for my project?
Here is my project thus far with a temporary / hard wired battery for testing. I still need to add a 3d printed panel with mHDMI and mUSB female connectors and the power input for the charger circuits.
- adafruit_support_bill
- Posts: 88154
- Joined: Sat Feb 07, 2009 10:11 am
Re: Using a system while charging it's battery
You don't need a solar panel to use the solar charger. It will also accept power from USB or a 5-6V DC power supply.
This guide shows several connection options for multi-cell charging: http://learn.adafruit.com/multi-cell-lipo-charging
This guide shows several connection options for multi-cell charging: http://learn.adafruit.com/multi-cell-lipo-charging
- chisleu
- Posts: 18
- Joined: Sun May 26, 2013 9:41 am
Re: Using a system while charging it's battery
Clearly there is something I am missing because I don't see how any of those circuit examples will keep my system from rebooting when you flip the switch. There will be a momentary interruption in power if I understand that correctly. What I'm looking for is a method to plug in a charger cord which will start powering the circuit while charging the batteries. I see that the solar capable charger does that. I would love to add a solar panel to the top of my system, provided I could split it's output to both charger boards. However what I need to know is if this example will work.adafruit_support_bill wrote:You don't need a solar panel to use the solar charger. It will also accept power from USB or a 5-6V DC power supply.
This guide shows several connection options for multi-cell charging: http://learn.adafruit.com/multi-cell-lipo-charging
Here is a link to the circuit I'm describing: https://docs.google.com/file/d/0BwteEg8 ... RvME0/edit
Could I wire it like so to allow for a single panel slowly charging when possible, and a auto-switching 5v input / charging setup with a 7.4v output voltage for my load?
- adafruit_support_bill
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- Joined: Sat Feb 07, 2009 10:11 am
Re: Using a system while charging it's battery
That circuit won't work. If you want to charge 2 batteries in series, you need 2 chargers. Each of those chargers needs a separate power supply - otherwise they would have a common ground and short out one of the batteries.
- chisleu
- Posts: 18
- Joined: Sun May 26, 2013 9:41 am
Re: Using a system while charging it's battery
Since I'm not going to have two power supplies for the device, then I need to find a 7.4v charger instead?adafruit_support_bill wrote:That circuit won't work. If you want to charge 2 batteries in series, you need 2 chargers. Each of those chargers needs a separate power supply - otherwise they would have a common ground and short out one of the batteries.
Zut! I was excited about the prospect of using a solar panel.
Thanks for your help.
EDIT:
If I change to use a boost converter, I could use http://www.adafruit.com/products/390 and http://www.adafruit.com/products/500 .
I would have to rig a voltage monitoring / LED scale setup. Maybe there is something I can work out. Again, thanks for your help.
Please be positive and constructive with your questions and comments.