eBay adjustable CC/CV module for 4.3v cell charging?

My module came today with Swiss post.
Sadly I have just build something different with my battery holder…

Thanks for share this info, I have one of this circuits…


I like these cradles, I can solder everywhere so resistance is no issue. Just glued the circuit with a bit of hot glue on top.
The voltage pot seems indeed a bit touchy, or maybe my multimeter isn’t good enough for measuring hundredth of volt.

I accidentally connected a flat-top battery the wrong way because it was too dark and I was careless.

Lots of smoke and bad smells ensued. I saved the battery (only dropped down to 3.64V from 3.98V) and the next day I tested that the internal resistance was barely a few mOhms higher than the rest, so I charged it back up and it was fine.

But I've bought meself a slightly different one with voltmeter and ammeter built in. I bought two.

Also, to safeguard against my stupidity, I bought a toggle switch and a circuit breaker.

I figured that a battery protection PCB wouldn't work properly if the battery itself polarity was reversed. Looked into some diodes, including shottkies and non-synchronous rectifying circuits, but they all were designed for the battery to be the only source and the protection only hand in mind the power coming from the battery.

So only circuit would be set at 4.29V, the other at 4.19V, the toggle switch would be on the input side of the charging circuit, and the circuit breaker on the battery side of the charger. Pics when done.

Ramblings. What are the white connectors on the ends of the displays?

I actually have no idea.

I can't take a picture of mine, because I fried the first one, but when it was functional, all I did was connect the in and out using the screw junctions and everything worked fine.

I'll get out my multimeter and check when I get the next one.

oh wow…nice find!

Thanks

Came across these…built in displays for input and output voltages w/ ammeter 5A
(a little more pricey than the ones without the display)
2PCS - $15.96

I Use these for my pink LG,s works very well I quick charge with my hobby charger first then finish with this little module.I parallel 4 batts at a time .

I wonder what the serial interface is…in the picture with the laptopbattery it is connected…?
Has anyone more information?

Single piece for 8$ http://www.ebay.com/itm/5A-Adjustable-CC-CV-Display-Step-Down-charge-Module-LED-Panel-Voltmeter-Ammeter-/400544557141?pt=LH_DefaultDomain_0&hash=item5d4250e855&tfrom=400691989349&tpos=unknow&ttype=price&talgo=origal

Do you happen to repurpose packs in that way? I wonder how best to interface with the blade connector.

Good link, thanks. I’ll wade a bit deeper into that thread soon!

Maybe you guys could request a “free sample” charging board from Texas Instruments

4.3vdc Li Ion Charge Controller chip

I don’t think those are SMBus. As you say, SMBus, which is based on I2C and can support multiple devices, uses one line for clock (SC), the other for data (SA). The lines on that PSU are labelled RXD & TXD, which looks more like a traditional bi-directional serial port.

Has anyone explored that power supply further? I think someone on Youtube mentioned that they couldn’t get anything interesting to happen with that connector.

I have one of those 10 A buck converters and that was my plan b for my project if i failed to pas 1 million cd with 4.2 volt. i was going to use 2x18650 in series and get whatever desired current to the led with using it. it looks a very decent driver this only that have to be careful with output range you set up otherwise i broke one xml t6 very easy with only 5v input. but i succeed in my project so i have this driver waiting for something else now :slight_smile:

Charge pattern per cell in a Li Ion is almost identical to that of a properly charged lead acid battery (which just happens to have 6 cells in it

The current goes down on its own as the charging medium saturates (thus the full point being the current flow is not 10% of the battery capacity) , the constant current is there to limit MAXIMUM charge rate, otherwise just limiting voltage charging could be easily done with a constant voltage regulator, but the amount of current the battery will absorb initially will very large, dangerously large if not limited)

Notice the constant current dashed portion of the graph, voltages are different per cell naturally, but the constant current aspect is the charge pattern that determines the “fullness” of the battery

I use one of these to charge my daughters 6vdc lead acid battery in her little power wheels car, set to 2.35vdc per cell, then feed the output thru a HF multimeter, short the leads adjust max current rate to say 1A or less, then tie into the battery, you can watch the volts drop, current goes up…but after a while as the current draw lowers the voltage levels out at the set rate, then as the current decreases to around 10% of maximum rated mAh of the battery, then its full, nice thing is with lead acid you can set a float voltage or approx 2.25vdc per cell (13.8 for a 6 cell “12vdc lead acid battery” and leave it indefinitely as the battery no longer absorbs current at the lower voltage setting.

In fact if you charge at 4.2vdc, you can “float voltage” a Li Ion cell at 4.1vdc but the Li Ion chemistry and construction is very different and complex…it’s best to just charge then remove the charge from Li Ion where lead acid can be floated indefinitely

You can charge a 4.35vdc Li Ion cell on a 4.2vdc charger, it just won’t saturate fully, or ever maximum charge, it will be perfectly fine to use but won’t ever be at it’s full maximum mAh rating.

Manually charging a battery is possible…but it must be monitored CONSTANTLY, these Li Ion chargers the IC does the monitoring for us

They do offer Li Ion charging IC’s that charge at 4.35vdc…but you have to build the board yourself

Take this charger above, gut it, tie in the above linked charging module w/ a 4.35vdc MCP73834 (the MCP73833 is the 4.20fixed output chip) and it will charge those batteries at the correct CC/CV rate (also the Xtar MC1 is a good little host unit as well)

More or less this

The MCP73833 and MCP73834 are both available in the 4.35v flavor, the suffix is actually the designation to look at: MCP73833-NVI/MF

The “I” designates temperature range (for the safety cutoff I think?), the MF designates the package as DFN, and the NV tells us everything else: voltage, termination current, preconditioning current, safety timer, recharge threshold, etc. If there’s a pattern, I don’t see it: the two letter code used seems to be an arbitrary code assigned to a particular set of options. The only 4.35v option is “-NVI/MF”.

I’m going to be putting together a little charger using the one RMM sells. For those that have this thing, how hot does it get at around 2amps? would it be fine in a small enclosed container?

Now for a question on the voltage overhead: If I were to add a female micro-USB connector as a secondary input, would it work at all on a standard USB charger as a power supply? Just ad a reduced rate? Or do I absolutely need more overhead than that?

Hi everybody. First post here. I found this post while looking for an affordable way to charge a second battery I got for my Dell. Right now I have to charge the firts battery, remove it, put in the second one and charge it. I looked up the chargers over the web and they go for more than 60$. That’s a a steal. So I continued my search and found this little controller here, 6$ now :slight_smile:
Question: Where did you get the laptop battery connector you’re using. I will start looking for one now but wanted to know if you have a quick link for me. Thanks.

This topic is old but, well… maybe someone could guide me. I have a module of these, LM2596 / LM2577, and would like to use it, not for charging batteries, but as regulator for an adjustable power supply, based on a power supply for ATX computers, for small experiences.

I intend to feed the module with 12v, to replace the trimpots that regulate the voltage and the current by potentiometers of the same value (10k), and fix these potentiometers in the panel of the adjustable power supply. I also want to adapt an LED on the panel that indicates when it is necessary to increase the current. For example, if the load requests 2A but the current adjustment potentiometer is set to 1A, I’d like this LED to light up. In other words I would like this LED to light every time the load requests more current. My doubts are:

1 - Which of the LEDs should I transfer from the PCB to the panel?
2 - How should I set the middle trimpot to turn on that LED each time the current is insufficient?

Thank you.

P.S .: Please excuse me for the English “Google Translator” and please, if I have not been able to make myself understood, ask me what is necessary. Thanks.