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View Full Version : Charging profiles / smart chargers



DaveAK
25 November 2010, 1257
So I know the basics about charging - constant current until voltage is reached and then constant voltage and the current decreases to zero when charging is complete. Depending on chemistry you might have a pre-charge stage to bring all cells up to 20% or so, and a post-complete float/top off/trickle charge.

What do "smart chargers" actually do to facilitate this? The reason that I ask is that my charger is made up of four 24V PSUs, adjusted to give 88V or so @ 16A, (about 0.25C for my cells). It works as a CC/CV charger and when the cells are at max voltage the current starts to reduce. There doesn't seem to be anything smart about this to me - the cell chemistry itself is what determines the point at which CC switches to CV, right? I know a figure of 70% or so is quoted as this change point, but I don't actually configure it.

So beyond setting cell voltage and quantity of cells what else would you need to make a smart charger smart? Does it really need to know too much about charging profiles or actual cell chemistry?

Note: I do have my charger connected to the HVC of my BMS, so that when a cell trips the HVC the charger switches off. If this was to be a function solely of the charger then you would need to add the ability to monitor individual cells to the charger, which would make it smarter I guess.