Understanding Jumper Pack Peak Amps Ratings

The Truth about Jumper Pack Peak Amps Ratings

One of the key specifications you’ll encounter when shopping for a jumper pack is its peak amp rating. This article will delve into what the jumper pack peak amps ratings mean, why they don’t mean anything, and how to choose the right jumper pack based on real power ratings.

What Are Jumper Pack Peak Amps Ratings?

The peak amps rating of a jumper pack refers to the maximum amount of current (in amperes) that the device can deliver during a short burst. Unfortunately, there is not industry definition for jumper pack peak amps ratings, so it’s a useless term when shopping for a jumper pack.

According to executive Jim O’Hara from Clore/Solar, a major manufacturer of commercial-grade jumper packs,  “Peak amps don’t start engines.” Jim’s right. Each company can devise its own test to measure peak amps, making the term meaningless. It can mean whatever the jumper pack manufacturer wants it to mean.

Jumper pack battery ratings must be standardized for them to mean anything

To properly rate a battery’s jumping ability, you have to test it using an industry-defined test that accounts for battery temperature, a minimum voltage, and an industry-defined period. For example, here’s the definition of cranking amps:

Cranking amps definition

Cranking amps (CA) refers to the number of amps a battery can output at 32°F (0°C) for 30 seconds while still maintaining at least 7.2 volts. A jumper pack battery that has a Cranking Amps rating is more meaningful than one with a peak Amps rating because cranking amp testing is an industry-defined standard. It’s measured at 32°F because you’re most likely to use your jumper pack when it’s cold outside. Temperature is important because batteries produce power through a chemical reaction and that reaction slows when it’s cold.

In addition to temperature, you also want to know how long a battery can output the specified number of amps. Think about it: What good is a battery that puts out more amps but for such a short period of time that it can’t start your engine?

Finally, a jumper pack that falls below the minimum voltage required to operate the starter motor, is a jumper pack that’s pretty useless. That’s why cranking amps cover total amp output at a set temperature, for a set period of time, all while maintaining a voltage above a set minimum.

A Jumper Pack’s Cold Cranking Amps Rating Is An Even More Meaningful Measure Of Its Power

Cold-cranking amps (CCA) are like CA except that the rating is based on amperage output at 0°F (-17.8°C).

A Peak Amps Rating is meaningless

So if a jumper pack manufacturer says their pack puts out 900 peak amps, do we know how the test was conducted? Do we know how long the test was for? Do we know what battery pack voltage fell to during the test? If not, the peak amp term means nothing. millisecond?

You can’t even use peak amps to compare one brand of jumper pack to another since each manufacturer’s testing method may be different. That makes jumper pack peak amp claims even more dubious.

One manufacturer’s 1,300 peak amp battery pack may not start your engine, while another brand rated at 800 peak amp might.

©, 2020 Rick Muscoplat