# LIPO top balancer

hello, ive, never coded besides a few lines that was required for my 3d printer a few years back... I have a project that I need to accomplish for a electric drag racing battery. obviously many packs are wired up together to get higher voltages and amperage outputs, but I am only concerned with 1 - 6S pack for this initial circuit.

what I need to do is: test voltage between 1st and 2nd balance wire, if its below 4.15V, it gets hit with the 1A @ 4.2 until it shuts off... if its above4.15V, it skips to next cell... so moving onto 2nd and 3rd balance lead for 2nd cell. test voltage and either charge or move on. so on and so forth to the 3rd and 4th, 4th and 5th, 5th and 6th, and 6th and 7th balance leads

after 2 1/4 mile passes, the cells will be drained with a bottom balancer, b4 being bulk charged, and then this circuit will eventually run, say every 20 minutes, through all the individual cells of all of the 6s packs in the complete battery. so while the car is sitting in the pits waiting to make the next pass, it will go our completely topped off.

so this is going to be a top charger, or lipo trickle charge...

I have a few of these 6s packs, an adafruit powerboost 500 and an arduino, but other than that, im a sitting duck.

please feel free to shed some light on this situation! seems there is a lot of stuff about lipo and charging, but not quite this type of application... or I might just be looking and searching for irrelevant topics so forwarding a topic is plenty helpful too!

thanks in advance for any your consideration and any contributions to my project!

Hi, Balance Wire? ? ?

Tom.... :)

yes balance wires. the wires on a battery that allow you to check the voltage between each cell when cells are in a series string... so to measure voltage of each cell individually, i need to use the balance leads...

anyone else?

Hi, So you need to measure differential voltages between the series array connections to calculate individual cell voltage.

Sorry just terminology.

Earlier this year in this forum a similar question was asked, try the "Search the arduino forum" window on the top right hand corner. If I remember there are a number of IC's that will do you job, the problem is the maximum voltage of the array and getting sufficient AtoD resolution. Due to scaling before AtoD as the Arduino can only AtoD 0 to 5V.

Tom...... :)