Last charge for my 3 LiFePO4 cells pack

As explained in my last post, it is time charge the 3 LiFePO4 cells pack again, but for the last time, because now I think I tested them enough and will put them for sell online

I do not know if I already wrote this, but I am using two 12V Mascot chargers in parallel to charge twice faster this pack, and, of course, I am carefully following the voltage using my Bottom Balancer for this as a voltmeter

A clear indication of the voltage

The two Mascot (Norvegian) chargers working together

Parallel charging and single cell voltage reading

Measuring my last Mottcell LiFePO4 cells

As I already wrote few weeks ago, I made a 3 LiFePO4 cells pack with them, bottom balanced them, charged, and discharged them few times by plugging in an iPhone / iPad 12V charger, which downstages voltage to 5V anyways (so it does not have to be 12V really to work, it could be 2 cells actually)

Few days ago, around diner time, I checked the voltage of each cell, because it had been more than two weeks and we had been charging our iDevices on this mostly

You can see here the benefits of bottom balancing the cells before the first pack charge: we are reaching the lower limits of the cells and they are still in balance, coming down together:

Voltage measured still under load (iPhone is plugged in as you can see)

Cell 1 = 2.94V

Cell 2 = 2.93V

Cell 3 = 2.92V

Pack  = 8.80V

=> So, no problem, and after reffilling my iPhone fully, it will be time to recharge the pack 

Exercising the remaining 3 Mottcell LiFePO4 cells

After selling my Enginer Prius PHEV Kit 32 LiFePO4 Mottcell 39Ah cells, these are the only good cells left, and I am "exercising" them by Bottom Blancing them, Charging them and Discharging them

For that I use my home made small (and cheap) Bottom Balancer, one or two Lead Acid Chargers and of course watch carfully so that I do not overcharge them, and for that I use the Bottom Balancer as a voltmeter display only, leaving the load/resistor switch OFF

For Discharging I found a way to re-use the energy by wiring the 3 cells pack to a 12V car socket, and charge iPhones and iPad with it, slowly draining it; The pack is 3 x 3,2V nominal which shows 10V more or less fully charged and I will stop when it reaches 3 x 3V = 9V and will recharge from there

Eventually I will sell these 3 cells after checking that they are fine ... and they seems to be ...