Designing Constant Current (CC) for LiFePO4 Battery Charger
I want to design a charger that charges my lifepo4 battery(4s,3p). The charger is going to be AC to Dc charger having an output of 14.6v 15Amps. My challenge now is i intend to ensure i have a CV,CC at the output, the CV can be done easily, but the CC, i am having difficulty wrapping my head around how to go about it.I studied the XL4016EI circuit to see how they achieved the constant current functionality using variable resistor to set it, but i dont want to use that IC for the CC functionality.I want to incorporate the functionality of CC but have no idea doing it. The IC I am considering to use for the fly-back converter is the UC3842/UC3843.
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Charging lifepo4 is more than just CC/CV, you have maintain the charge curve, trickle charge, etc. Any mistake and you will ruin the battery. I would recommend buying a off the shelf charger for the job. Also you could reverse engineering the commercial product if you really want to design a charger
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Solution
Charging lifepo4 is more than just CC/CV, you have maintain the charge curve, trickle charge, etc. Any mistake and you will ruin the battery. I would recommend buying a off the shelf charger for the job. Also you could reverse engineering the commercial product if you really want to design a charger
Thank you for this, can you throw more light on the charge curve? i intend to use a bms to protect the battery also. About trickle charge, is it really necessary to apply trickle charging in lifepo4 battery?
Not really familiar with lifepo4 battery, but I have read datasheets about lipo battery charger IC and they come with loads of protection features to ensure battery safety. Also can check some TI lipo/lifepo4 battery charger ICs. Most are rated for 1s 1A range, but if you keep digging you will find ICs that connect to external mosfets that support higher amperes
Thank you, I'll keep digging