AT Pro Li-Po conversion

[G(old) digger]

[attachment 229921 DSCN0066.JPG][attachment 229922 DSCN0068.JPG]I recently converted my AT Pro to use Li- Po cells. Using 2 cells has a nominal voltage of 7.4 and a peak of 8. I checked with Garrett and they thought the regulating circut could handle the higher voltage, which so far seem's to be true. Already having the proper charging and balancing equiptment I only needed the 2 cell Li-Po wich cost's $20. The advantage is the detector is operating at it's maximum voltage instead of the nominal 4.8 volts from NiHi or NiCad rechargables, also no memory or voltage decay characteristics. They can be recharged in under 1 hour. The disadvantages are they can burn like a flare if not handled an charged properly and if shorted direcly can destroy the cells. I am not endorsing this conversion totally due to the critical characteristics of these cells and the cost of the charging equiptment cost ($75-$100) and the small amount of time i've been using them.




AT-Pro, GTP 1350, Freedom Ace Plus, Pistol Probe, Vibra Probe.

 

[mudpuppy]

One thing about this sport is the amount of creative people that undertake a project like you just did. I think its awesome for you to attempt it, and share it with pictures!

 

[flbowhunter]

Great Idea, I use Lipo batteries all the time as I and my kids are also RC car and truck fanatics. As long as you keep the Cell's happy (balanced) they are awesome. My question to you is since you are not using a speed control to detect the lipo cut-off voltage as we do in our RC car hobby, do you just keep checking the voltage with a meter?? They should not be discharged below 3.2v per cell or irreversible damage may occur to the cells or worse. In one of my sons RC's I wired a cutoff switch in-line, and when the battery gets to the "magic" 3.2v/cell it cuts the power and flashes a blue LED to let me know when to recharge. I think you should be fine if you just test with a meter, as the AT Pro won't draw the amps as an RC brushless motor will. I may have to try this with my AT Pro now. Good post.

 

[SteveP(NH)]

There is no advantage to supplying 9 volts versus 8.4 volts to the regulated power supply. The whole point of a regulated power supply is to keep the supply of power to the circuit the exact same regardless of the input voltage as long as the voltage being supplied is above the cut off voltage of the power supply.

 

[Leonidas]

Can I use something like that? (store in back bag) http://www.mediafun.ro/upl/manuals/6v_12ah_ultracell.pdf
What do you thing? Before use, must modify battery holder to make the connection.