How to use a Protection Circuit board? [Solved]

Other Hardware General Electronics
1

Hello again! I ran into another snag in my project. I am using two 3.7v 5000mah batteries (Protection Circuit Module (PCB) for 3.7V Li-Ion Battery (5.0A limit)) wired in parallel. I knew that I needed a PCB (Protection Circuit Board) and I was suggested to buy this one (Polymer Li-Ion Cell: 3.7V 5000 mAh (896474-2C, 18.5Wh, 10A rate), UL listed/UN38.3 Passed (NDGR)).

My problem is that I don't know how to use it. I gathered from the different articles that I read that I would attach the positive and negative ends of my battery to the B+ and B- respectively, and then my new output would be P+ and P-. I get no response when I connect my multimeter to P+ and P- while the battery is connected.

Are P+ and P- supposed to act as a new output for the battery, or do I only need to connect the PCB when charging? That explanation that I just said doesn't make any sense since the PCB is also supposed to protect the batteries from discharging too much.

Thank you for taking the time to read this! I'd be nowhere without the help of friendly community forums!

2

JohnLincoln:
Your link to the protection circuit is wrong, you've duplicated the one for the battery. Could you give us the correct one, please?

Sorry! I have the correct link now.

3

Your description of how to connect the protection PCB is correct, according to the specs at http://www.batteryspace.com/prod-specs/1249_5.pdf

Did you solder the battery connections?

What is the voltage at B+ and B-? If that is within the correct range (> 2.4 V and < 4.3 V) and the output from P+ and P- is zero, then the PCB may be defective.

4

Almost all Protection boards i have seen, defaults to be in "protected" state when the cell is connected. You need to connect a charge voltage on the P-terminals to "wake" it up. Around 4 volts that is.

// Per.

5

Zapro:
Almost all Protection boards i have seen, defaults to be in "protected" state when the cell is connected. You need to ceccect a charge voltage on the P-terminals to "wake" it up. Around 4 volts that is.

// Per.

Thanks for all of the suggestions! Zapro's was the one that work though.