(I hope it's the right category, not sure )
I'm looking for help designing/improving the logic behind my idea to make a full auto 12v battery cycler.
Full auto, because then i can just leave it in my garage doing its work all alone.
The cycler would work like so: first it asks the user for 2 options to start from.
First option is to start charging the battery,
The second is to start discharging first. If you select the first option, it asks the charge end voltage and CC(constant current). if it finishes charging it would beep, wait about 20 seconds, and then start the discharge proccess with default CC and end voltage.
if you choose the 2nd option, it asks for discharge CC and end voltage instead, if it finishes discharging, it would again beep, wait about 20 second, and then start the charging with default values. I'm sorry if it was hard to understand my basic logic, i have made a plan too, for visualising things.
i Should mention that in my head i have all the parts lyin' around on shelfes, all exept the power mosfets if i want to limit discharge current, could do that with an l298n tho.
Here it is(hopefully)
What are you asking? What would the benefit be? From you are saying you will charge and discharge a 12V battery on a regular basis possibly timed. It would be a fun project but all batteries have a finite life and that limits the number of charge/discharge cycles. Each cycle will diminish the battery life maybe by a miniscule amount.
The thing is i have a bunch of deadish batteries, i've read somewere, that if i charge them long enough with a small current, they MIGHT come back, probably not. i was thinking of cycle testing them to see how bad and stable the capacity is, but i don't want to discharge them fast. And thats the reason to automate the process, so i don't have to constantly keep an eye over them.
if it works well, i might build multiple ones. Mostly asking for help with some code problems, like how would the arduino know if that battery stopped accepting more charge? i wouldnt say i'm i total newbie, so i don't mean that some1 would do the code FOR me.
Seems to me you want to switch between a static load (draining the battery) and a charger, and during the process, both drain and charge, you want to measure the voltage of the battery, to decide how to proceed.
Sounds like quite doable. You will need to create a voltage divider to bring the max voltage, safely below 5V, and scan it via one of the analog pins of an Arduino. For a 12V battery, assuming an absolute max voltage of 20V (14.4 is usually (?) max charge voltage), you would reduce voltage by factor 4. I assume you know how to do a voltage divider. Using high ohm resistors, there would be no signifcant leak.
Now, measuring Amp Hours, you might be using an current sensor, although I don't know their precision. But if you discharge through a fixed resistor, all you need is continously measuring battery voltage, and use Ohms law to calculate the amperage.
Good luck, sounds like an interesting project.
Oh and note that a lightbulb is NOT a constant resistance device
Your idea sounds useful. I have seen a roomful of batteries being conditioned while plugged into an app that monitors, directs, records and plots every useful statistic. Sounds interesting.
Yep, basically my plan, but i'm also adding a LCD, SD card slot for logging, buttons, beepers and that stuff. Interms of measuring current, i would like it to be accurate, bc not all my batteries have big capacity. so the small the AH, the more precise the current has to be. i was sceptical about the lightbulb idea too. and i'm gonna try to stick with the ohms law idea.
Thx for the positive feedback, i'm gonna continue with that project tmr.
thx, and also, bc i didnt see such projects when doing my research, i might do an instructable on it, if it works and such. i might even make multiple ones of these testers, bc i get dead batteries all the time from my dad's car repair business. maybe i'll compact the design, bc i only hvae 1 mega, and the uno might or might not have enough I/O. i could replace the screen with some LEDs..
The only chemistry that I know of that could benefit from a discharge cycle is Nickel-Cadmium. Flooded car batteries and maybe some sealed ones could benefit from overcharging.
Discharging old car batteries below 50% would likely kill them (high self-discharge). Some reading material.
Leo..
I will not interfere and add more suggestions. Just want to take my hat off for Your presentation in the pictures! Impressive.
Way too often tons of confusing word sallad is used!
It's an interesting project. Know that different "dead batteries" need different tactics. I suppose You have used Google to pick up what's already has already been investigated.
You'll solve this!
Dead car batteries only need one treatment: The recycling bin.
To pick out the car batteries that have been replaced wrongly, I would just charge them and let them sit for a month or two. If they still are 12volt, then they can be re-used. If not...
Leo..
Suggestions? I would have liked to atleast hear them. and yes, i want to be different, i have read many, MANY, forum posts with no punctuation marks. i want to make myself understandable, even if i don't speak english natively. i'm not even 18 yet.
that's fair, yes the ones i dont need are gonna go for scrap. i'll pick one or two with the best cosmetics, and convert them to 18650s. and the ones i somehow manage do keep alive(idk how tho), i'll just have them around, i have many car audio projects.
even if 1 cell is bad, a head unit will still work, yes the big amps wont, but my big amp is broken anyway. srry for off topic.
yep, i saw some 8y old video, that showed u need a dumb old charger that will overcharge the heck out of a battery. i even have these chargers. not that old tho, i have some 90s ones. i could diy one also(what it is?) 4 diodes and a transformer. thats it. yes yes also a fuse before the battery is highly reccomended.
Yes, You're right. But! For large lead batteries the pack is checked for bad cells that are usually exchanged. For such a battery not being maintained (filling water) that has ran dry, the "solution" is the same, recycling.
My thought was for the case of dealing with, expAanding to, other technologies like LiPos of different kinds. Being ran down chargers refuse to charge them but several people claim there are methods.
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and yes, i want to be different, i have read many, MANY, forum posts with no punctuation marks. i want to make myself understandable, even if i don't speak english natively. i'm not even 18 yet.