You need to find the group size of the battery for your specific 2001 Ford Escape V6 XLS. This is usually stamped on the top of the battery itself, and is a code like "Group 47" or "Group 51R". Once you find the group size, you can then look up the recommended CCA and Ah ratings from a battery retailer (like AutoZone, Advance Auto Parts, etc.) or your owner's manual.
The CCA rating is the more important number for starting your vehicle, while the Ah rating indicates how long the battery can power accessories without the engine running. A higher CCA is better for cold starts, and a higher Ah is better for longer accessory use. The recommended ratings will depend on the climate you live in.
