hi i am hoping for some help as i am unsure what batteries to use for a project. I am planning on making a remote control vehicle controlled by a wireless wii nunchuck and am unsure what batteries to use to power it below is what i am thinking so far some critique or reassueance would be great.
arduino uno board with wichuck adapter plugged into wireless wii nunchuck adapter connected - powered by 6*AA rechargeable batteries with battery holder connected to barrel power connector and plugged into the arduino dc barrel connector
adafruit motor-shield r3 connected to 4*AA rechargeable batteries into screw terminals, the motors are the ones that come with the sparkfun magician chassis (comes with 4AA battery holder) JetBot Chassis Kit V2 (ROB-17279) - Proto-PIC the datasheet for this says:
Suggested Voltage: 4.5V DC // i assume this means that I need 4.5v overall not for each motor i.e 9v
1?No Load Spedd: 90±10rpm
2?No Load Current: 190mA (250mA MAX)
3?Allowable max. Torque: 800gf.cm mi
for the batteries i was just planning on using the decent ones with the highest mAH rating i could find
is this set up OK. I am OK at coding but don't have much experience with electronics and don't really want to blow anything up. i apologise if this topic is covered elsewhere but i have looked and cant find anything I understand that clearly. I was hoping to use lithium but these all seam to be 3.7v and then jump to 7v+
many thanks and sorry if this is a stupid question
Focus on the stall current which is the maximum current the motor will consume under its maximum load. That's 1A (or 1000mA). To drive two motors at full power for one hour you need 2Ah (2 amp-hours) or 2000mAh. An AA, rechargeable, NiMh battery just happens to be around 2000mAh.
You can use a battery greater than 6V with your motors if you just limit the current to them; of course this is easily done with a motor shield by simply not running them at max power. If you're not sure if you're running them with too much power just feel them and see how hot they are; if they're hot then supply less power.
Chagrin:
Focus on the stall current which is the maximum current the motor will consume under its maximum load. That's 1A (or 1000mA). To drive two motors at full power for one hour you need 2Ah (2 amp-hours) or 2000mAh. An AA, rechargeable, NiMh battery just happens to be around 2000mAh.
Just to be clear, this is only under "ideal circumstances" - ie, not anything you would see in the real world.
If you look on the spec sheet a given battery, you will usually see a graph or equation for battery capacity "de-rating", generally due to heat (externally and internally generated), though other factors can come into play (heat is the main factor, though).
So - the best way to know is to find a given battery or cell of the capacity you think you'll need, look at the battery de-rating, and recalculate for the conditions you expect or think the battery will see (and adjust your sizing accordingly).