- August 15, 2016 at 2:38 pm #3653SteveParticipant
Can you explain the differences in the battery options?August 15, 2016 at 3:47 pm #3654SuperDroidKeymaster
When selecting the batteries for the your robot there are certain things to consider.
Voltage: Some of our kits have 12V and 24V motors. If you are using 24V motors, you will need a 22.2V or greater battery for voltage or run two 12V batteries in series.
Capacity (Ahrs): The next thing is run time. All our motors have a data sheet attached to the item page that shows the current draw. the motors should run in the working current range for best performance. This current times the number of motors will be the nominal amps consumed. Now if you are doing pivot turns or running up hills, etc. the motors will draw a lot more current. It will also depend on your duty cycle (ie if you run for 15 minutes then sit for 45, thats a 25% duty cycle). So say the working current is 1A per motor, 4 motors will be 4A, so with a 10Ahr battery, you will get about 2.5hrs at continuous duty, 5 hours with 50% duty. This is not an easy thing to calculate ahead of time until the robot is built and you measure the current that is being consumed during normal operation, but its a ball park approach to size the batteries. The more Ahrs the battery has, the longer your robot will run (however, the weight will go up some too, which will slightly effect your current draw).
Max Discharge: The last thing you need to consider is the maximum discharge rate (the C rating). sometimes the battery will just state the maximum current the battery can discharge and charge at, other times its a C rating. All you do is take the C rating times the amp hours of the battery. So a 10Ahr battery with a 10C rating, can handle 100A. Look at the stall current of the motors and make sure all your motors stalled do not exceed this value or you will damage the battery over time, go way over it and you may damage it immediately. The batter batteries will have overload protection.
Qty of batteries: We have quantity of batteries offered too, which as mentioned above if you are running 24V, you will need two 12V batteries. You can also run batteries in parallel. Two batteries run in parallel will keep the voltage the same, but will double your amp hours and double your rate of discharge.
Most of our robot kits we only provide options for batteries that are suitable for the platform, so you just need to pick the right voltage (or qty of batteries to get the right voltage) and the Ahrs for the desired run time. We typically have the recommended best solution defaulted on our robot kits. If you need specific help, we need to know what robot, what options, what motors, what wheels, what terrain, duty cycle, etc. and we help you select a different battery option.September 21, 2016 at 11:02 am #3786ThomasParticipant
Thanks for the info!January 24, 2017 at 2:59 pm #4013
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