Hot Rod your old Dustbuster

Step 5 Charging setup.

Here you can see my new and improved charging setup. I used an old dead RC pack's deans connector so it would easily plug into my RC charger. This allows me to charge the batteries with more care than the original dumb charger that fries cells over time. Keep in mind that the polarity is opposite of what you expect, since you're charging not discharging. And I did bypass the diode in the charging base to allow unrestricted intelligent charges.