After some research on DIY arduino controlled chargers on the internet I could not find something that included what I had in mind. While visiting one of my friends he mentioned that he did a few DIY arduino based projects and will assist in trying to put something together. My idea is to use relays to control the load and AC to DC charger based on voltage readings( & settings), temperature readings for battery as well as temperature readings for the enclosure in which the setup is homed (environment temp). The aim is to use a laptop type charger and based on voltage readings, determine charge and discharged settings to maintain SOC levels between 10%-90%. I'm first to acknowledge that I'm a novice to this field and in the file attached I tried to put my logic on paper to demonstrate the functionality. I will appreciate any constructive comments or suggestions and/or possible challenges and issues that this logic might cause down the line. Thank you.
DIY Arduino controlled charger v1
- Thread starter Cdvan
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John Frum
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I'm also starting an Arduino based charge controller project.
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IoT Relay
Create the Internet of Things with safe, reliable power control. Universal control voltage 3-60VDC or 12-120VAC connects to Arduino, Raspberry Pi, PIC or other micro. Or connect directly to a 12V to 48VDC or even 120VAC circuits. High voltage wiring and safety hazards are eliminated. A single...
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curiouscarbon
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dear @Cdvan, cool project idea, i think you can go far with it! yea!!!
nice flow chart of charger function ?
after seeing your flowchart, one situation i could see a problem potentially arising (hehe potential because voltage) is if the battery becomes very deeply discharged and the system wakes up when AC power is supplied for the first time after long sleep.
if the laptop adaptor can provide 0.5C charge rate for the given battery setup, and the cells voltage potential are down in the basement cellar at 2.0V or something.. charging at 0.5C from the beginning could maybe reduce life cycle compared to charging very gently eg 0.05C from very low volt until 3.0 volt per cell or so.. then hit it with 0.5C the rest of the way.
if automatically handling this hopefully rare condition is appealing, (gracefully recover from deeply discharged battery), i think it could be achieved with just another smaller charger with its own separate mosfet or small relay from the primary charger, and a branch on the flow chart if cell voltage very very low.
please feel free to ignore this, my 0.02c (hehe that’s equivalent to 50 hour charge?)
nice flow chart of charger function ?
after seeing your flowchart, one situation i could see a problem potentially arising (hehe potential because voltage) is if the battery becomes very deeply discharged and the system wakes up when AC power is supplied for the first time after long sleep.
if the laptop adaptor can provide 0.5C charge rate for the given battery setup, and the cells voltage potential are down in the basement cellar at 2.0V or something.. charging at 0.5C from the beginning could maybe reduce life cycle compared to charging very gently eg 0.05C from very low volt until 3.0 volt per cell or so.. then hit it with 0.5C the rest of the way.
if automatically handling this hopefully rare condition is appealing, (gracefully recover from deeply discharged battery), i think it could be achieved with just another smaller charger with its own separate mosfet or small relay from the primary charger, and a branch on the flow chart if cell voltage very very low.
please feel free to ignore this, my 0.02c (hehe that’s equivalent to 50 hour charge?)
Thank you curiouscarbon for your input. You have raise a very valid concern if the voltage drop too low. My question is that if I set the Battery Low Voltage setting to 12V( 3V per cell) will this still be an issue? On all the charging charts I researched it seems that equates to about 9% SOC that seems to be OK using a 0.5C charge rate. Am I missing something?
I will also add a BMS to these batteries.
I will also add a BMS to these batteries.
