Aircraft NiCd Battery charger

I'm intrested in building a battery charger for "big" aircraft NiCd battery. I want to use Arduino as controller for special charge/discharge cycles. I need a tension measurement in order to start some duty charge or discharge, a current controller in order to charhge the battery at due Amps, a thermometer to check battery temperature and a timer to control overall situation an cycle time. Battery can be 12V or 28V, charge current can go up to 15/20A. Best way to charge battery is working on single cell, so I will need to control up to 20 cells (cell tension, charging time, charging amps, temperature). Final price shoult be lower than shop price, quality MUST be higher... as usual when you use Arduino ;)

I can't find a redy project on web so I need your brainstorming to find the best solution for this "game".

Many thanks to any... intrested brain. 8)

ciao diego

wow.. no so many intrested! :cold_sweat:

-ammeter: http://www.vwlowen.co.uk/arduino/current/current.htm

-timei is a no problem.

I'have no idea how to control current from a power supply... suggestions? thanks

diego3vsan: I'have no idea how to control current from a power supply... suggestions?

Take a look at http://www.timnolan.com/?page=arduino-ppt-solar-charger. I understand you're not dealing with solar but his circuit design implements both the current sensing and current limiting you need and he describes the circuit pretty well.

His arrangement of the mosfets Q1 and Q2 as an "ideal diode" is worth taking some time to understand also.

thankyou Chagrin!

isn't too easy to me but I'm reading this intresting article but I'm not sure I can use it.

I'm now planning to use an LM317. is full of examples on internet so... I will try!

kind regards diego