## jargon

• LiPo - Lithium-ion Polymer
• NiMH - Nickel-Metal Hydrid
• Discharge Rating

### Capacity

Capacity is denonted in milliampers hours (mAh) on the battery. It is the amount of charge stored in the battery. If you have a battery with a capaciy 1 mAh and a motor is drawing 1 mAh then your motor will run for 1 h. In general the \textit{approximate} duration of a battery can be computed by:

$\mathrm{duration} (h) = \frac{\mathrm{capaciy(mAh)}}{\mathrm{load (mA)} }$

If you have a 4700 mAh battery and it is powering a moter with a 100 mA load, it will keep runing for approximatly 47 hours. reference

### Battery bank

Combination of multiple batteries reference

• joined in series: voltage increases, capacity remains the same.
• joined in parallel: voltage remains the same, capacity increases.
• series and parallel: both voltage and capacity increase.

A guide to understanding battery specifications

RC battery guide

## Pixhawk 2.1 battery stuff

Power brick mini

• Max continuous current sensing: 30A
• Max burst current: 100A
• Connectors: XT-60

## Electricity

• Ampere: A - base unit. Attractive/repulsive force of $$2 \times 10^{-7}$$ Newtons between two wires 1m appart is the definition of $$1\,\mathrm{A}$$. $$1\,\mathrm{A} = 1\,\mathrm{C} / 1\,\mathrm{s}$$

• Coulomb: C - charge transported by a constant current of 1 A in on second. $$1\,\mathrm{C} = 1\,\mathrm{A} \cdot 1\,\mathrm{s}$$

• Electrical work is the work done on a charged particle by an electric field.

• Watt : W - power. $$1\,\mathrm{W} = \frac{1\,\mathrm{N} \cdot \mathrm{m}}{\mathrm{s}}$$

• Volt: V - pressure

• Ohm: $$\Omega$$ - electrical resistance

### voltage

$V = \frac{\mathrm{potential energy}}{\mathrm{charge}} = \frac{N\cdot m}{C}$

### Ohm

• Ah - ampere hour
• mAh - milli ampere hour