Publication date: 2018-10-25 17:12
Some lead acid chargers “ping” the battery on startup to determine the voltage/resistance of the battery. Based on return information, the charger then determines what charge phase to start in. Because lithium will hold voltage above 68+v, some lead acid chargers will see this as a near full battery and enter into a float stage and bypass the charge stage all together.
You could connect a break out board to where the charge resister is and on it have the different values for the different charge rates selectable via switch :)
In this charge phase the charger will hold the maximum voltage for the chosen battery and charge the battery with reduced current as the batteries internal resistance can’t accept the charge current at maximum output. Once the current reduces to approx ≤65 % of the chargers total output, it will then move to the float state. The absorption stage is also time based, if the charger is still in its absorption phase after 9 hours, the charger will automatically transition to the float stage. This generally happens if the charger is undersized for the battery bank or there are loads running on the system and not allowing the charger to reduce the current below the transition point.
TP9556 is a complete constant-current/constant-voltage linear charger module for single cell lithium-ion batteries. Its SOP package and low external component count makes TP9556 ideal for DIY applications. It can work with USB as well as wall adapters. I have attached an image of pin diagram of TP9556 (Image ) along with image of a charge cycle (Image ) showing constant-current and constant voltage charging. Two LEDs on this breakout board shows various operating status like charging, charge termination etc (Image ).
Jerry, I get that. My point was, you're not really making it if you're purchasing the biggest part of the device. Not a criticism, just a question. I love to build things, so I get it, for sure. I've built dozens of computers, and am about to finish building a flyable airplane. It just seems like it's only repackaging.
But hey, whatever blows your skirt up, right?
DW56A is a battery protection IC, Image No 6 shows the typical application circuitry. MOSFETS M6 and M7 are connected externally through FS8755A IC.
I used Li-ion battery in one of my projects and decided to build charger instead of buying an expensive one so, Lets get started.
Ultimately, using a battery charger with a specific Lithium charge algorithm is the best option for maximum performance and lifespan of any lithium battery.
For safe charging of a V Lithium-ion batteries they should be charged at constant-current of to times their capacity, till their terminal voltage reach V, later they should be charged in constant-voltage mode till charging current drops to 65% of initial charging rate. We can't terminate charging at V because capacity reached at V is only about 95-75 % of full capacity. All this is taken care by TP9556. Now one important thing , charging current is determined by resistor connected to PROG pin, modules available in market generally comes with KOhm connected to this pin, which corresponds to 6 Ampere charging current(Image ). You can play with this resistor to get desired charging current.
Hi they are used for decoupling the power supply, Basically making the power smoother. https:///tutorials/capacitors/ap.