I had this module in my mind for a while now.
Unless it is one of the new 48 modules that Gus mentioned recently I really would like to make that module. Anybody interested to team up on this one? I am pretty good with Eagle now. Having somebody with experience in charging/balancing circuits would help a lot. I think we can do it in a couple of days.
[quote]I’m particularly interested in having ‘fuel gauge’ properties available on the driver that let you know what’s left. Maybe even a 3 color LED that indicates good, needs charge, or nothin’ left.
Would you want a 3 color led, or an I2c or SPI fuel gauge so you code can know the exact voltage of the batteries.
@ jdal - by fuel gauge do you mean some sort of button activated 7 segment display? All I’m really gunning for is having the voltage available in software. Anything else is in the bling category (nice to have, but lets keep the cost down).
No, there are quite a few Charger IC’s out there that also have an I2C bus on them so you can read the voltage of the cells, charge current, drain current and few other odds and ends.
The power board would have a type “I” connector to support the I2C, so in your software you can read the battery information. Some IC’s have an IRQ line that you can set via software to trigger when the battery gets to a certain point.
Sure, nothing is etched in stone. The only reason i lean towards the 18650’s is that the protection is built into the battery, so there is never a worry about the customer draining the battery to low.
But you can use whatever you like.
Good idea… I had one build for a previous design where I used an EMX board. As battery charger I used i used the microchip MCP73831 and as buck-boost converter Texas Instrument TPS63001 for 3.3 Volt and TPS63002 for 5 volt. What I had in mind for a new design and might also be interested for a universal board are the following options.
an option to switch the power down by the micro-controller.
a possibility to power up the device with a tactile switch.
possibility to measure the voltage level of the battery, so that almost out of power can be detected by the micro controller.
how about this idea…
why not make it expandable… meaning that one can add as many batteries to it as they want…
using external magnets that would stick each extra battery at end, or on Top, or on the side or at the bottom of the module…
where each one would have it’s own electronics to charge it, in a way one would only worry about what each battery requires for charging instead of trying to balance the whole system, where the end result would give you the total amount of amps available from all batteries stuck to each other,.