LiFe Batteries

I’ve installed half the LiFe battery pack and controller (prototype).

LiFe batteries require some special control electronics to Charge and ‘Balance’, so this was quite involved (see picture). However they seem to work well.

My Battery Management System consists of all this, as well as a USB link to the computer so I can monitor the charge progress of all 5 Cells.

To test, I drove the boat for 30 minutes at mostly top speed, with two people (dad and I) on-board.

The battery pack is 17V, 100AmpHour, so I expected it to be half empty…

There was no noticeable change in Battery voltage (16.7), it doesn’t seem discharged at all..

This is a change from Lead Acid batteries, which noticeably change their voltage as they go flat (eg 13.6 Volts to 11 volts). The LiFe battery doesn’t let on that it is going flat at all..with only a small change from Full to Empty.

All in all, the LiFe battery had no trouble driving the boat around at 60 Amps peak, and didn’t go anywhere near flat.. from the Cell voltages, I would say I used < 30%. 


So, a summary of the test:

Battery voltage is good: 17 volts gets the boat to max displacement speed;  prop + motor + 17V is about right.

LiFe batteries are awesome,  last 3 or 4 times longer (will take 6 years for me to confirm this) than Lead Acid, voltage changes very little,

less than half the weight..Image

The Life battery 5 cells = 17 Volts




The Battery management system,

Charger, cell balancer, over discharge protection, over current protection, with USB connection for monitoring with a PC