Changes
* What kind of drive system requirements is needed?
These questions are necessary questions because of the variety of battery types available and the differences between them. The chart below lists the characteristics of the most common types of batteries. (Source [http://www.atti-info.org/technology/ev_tech.html])
[[Image:batterytypes.jpg|thumb|center|400px|Battery types by descending order of popularity]]
== Comparison of top 3 batteries used in HEVs ==
<blockquote style="background: white; border: 2px solid black; padding: 1em;">
{| class="wikitable" style="text-align:center"
|-
! Lead Acid !! Advanced Lead Acid !! Nickel-Metal Hydride
|-
| Low cost || Longer lifecycle than conventional lead acid || High cost
|-
| Low energy density || Valve regulated lead/acid (VRLA) batteries showing promise || Higher energy density than lead acid; not as susceptible to heat
|-
| Longer recharging time (6-8 hours) || || Shorter recharging time
|-
| Only fair cycle life || ||
|-
| Can be ruined by completely discharging them || ||
|}
</blockquote>
