Potential Energy in Fuels: How Does a Fully Charged Battery Measure Up?

Thread starter aaronb
Start date Apr 7, 2009
Tags

Energy Potential Potential energy

AI Thread Summary

A fully charged 15.0 kg lead-acid battery can deliver 1450 W for one hour, equating to a total energy output of 5,220,000 J or 5.22 MJ. To find the energy per kilogram, this value is divided by the battery's mass, resulting in approximately 0.348 MJ/kg. In comparison, gasoline has a heat of combustion of about 44 MJ/kg, highlighting the lower energy density of lead-acid batteries. The discussion emphasizes the importance of understanding energy outputs when comparing different fuel sources. This analysis aids in evaluating the efficiency and practicality of battery technology versus traditional fuels.

Apr 7, 2009

aaronb

Homework Statement

A fully charged 15.0 kg lead-acid battery can deliver power 1450 W for 1.0 hr. (For comparison, the "heat of combustion" of gasoline is about 44 MJ/kg.)

Battery _____ MJ/kg

Homework Equations

Unit conversion problem
1W = 1 J/s

The Attempt at a Solution

(1450 J/s / 15kg) = 96.7/10^6 = 9.6 *10^-5

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Apr 7, 2009

mgb_phys

Science Advisor

Homework Helper

How many Joules is 1450W times 1 hour ?

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