2S (7.4v) LiPo batteries: Can I use them?

Lynxmotion Rovers, Sumo, and Tracked
1

Hey, I just wanted to know if I can use 2s (7.4v) lipos with the rover without destroying anything. If so, does it have to be connected to a specific power port? I don’t need to charge or monitor voltages, I have external supplies for that. I just want to be able to run this robot without having to dismantle my lipo.

2

Coleman, can you suggest a charger for the DFRobot 7.4V 2200mAh LiPo battery?
Thanks,
Brent

3

Great, thanks for the information Coleman, appreciate it

4

Hi Coleman,
Just received the DFrobot 7.4V battery and the 9V wall adapter you specified in your email. I attached the battery to the Rover and it works great.
However, I’m unclear how to use the specified 9V wall adapter to recharge the 7.4V battery, as both have male ends. Could you let me know how?
Thanks again.

5

Great, thanks Coleman.

6

We have successfully tested the DFRobotShop Rover with the DFRobot 7.4V 2200mAh LiPo battery via the barrel connector, and then also with the Barrel to JST connector. The one consideration are the motors; if you have the original DFRobotShop Rover, the Tamiya gearbox has motors rated at ~3V, so using a 7.4V LiPo would damage them. You would need to upgrade the motors to 6V RM3. This also applies to the Mecanum version.

7

A 9V wall adapter should be able to charge the battery, but only if it has onboard protective circuitry and will stop accepting a charge when it’s full (which the DFrobot 7.4V does). If you are looking to become very active in robotics, we suggest something more universal: X2 Ultima Dual 200 Watt Battery Multi-Charger

8

That is often the case - you’ll need to adapt the wall adapter so it has a female end, or purchase a male to male adapter. Usually you can purchase a very inexpensive male/female plug / cable from a local electronics store. You would need to cut and connect the wires from the power supply and (preferably) solder the connector from the new cable. Be sure to not have the adapter connected to the wall when you cut the wires! If you have some heat shrink it would make the job look cleaner. Be sure to stick around the first time the battery charges.

9

I have the 6V motors and use a 2s 7.4 lipo pack just fine.

10

You can use a UBEC to drop down the voltage to 5v. You connect your battery to the UBEC and the UBEC to your board.