What size jump starter do you need
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So you have decided to by a portable jump starter and like a lot of first time buyers of portable jump starters the first question that people ask is. What size jump starter do I need? Before we look at answering this question we need to look at how the jump starter will be used. If you only have one vehicle that you wish to use the jump starter on then choosing a jump starter is an easier task, if however you have multiple vehicles that you want to be able to use the one jump starer on then you need to size your jump starter on the largest of the vehicles. You can use a large jump starter on a small car but you cannot use a small jump starter to start a large vehicle.
The size of the jump starter that you need depends on many things including: 1. Vehicle engine size. 2. Age of battery. 3. Weather conditions for your area. 4. Will you need one for multiple vehicles. 5. Agility to recharge the jump starter.
Armed with this information you need to look at the battery in the largest vehicle and note what the CCA value of the battery is. Most batteries will have this information printed on the side or top of the battery. If for some reason you can’t locate the CCA value on the battery you may find a recommended battery size for your vehicle in your manual.
Before we continue we need to understand what CCA actually means and why it is critical to sizing our jump starter.
Table of contents
Peak Amperes
Peak Amperes is the total amount of current a battery can deliver. It is not however very useful in helping you decide which is the best jump starter to start your car and in the most part can be ignored. What you need to know are the Cold Cranking Amperes (CCA) or Cranking amperes (CA) of the jump starter as these directly tell you how your jump starter will perform.
However if you also want to run accessories off the jump starter, via a mains power inverter or 12V DC Port, then peak amperes becomes important in determining how long you can run your devices before the battery in your jump starter needs to be charged.
Cold Cranking Amperes
Cold Cranking Amperes (CCA) is the amount of current a battery can provide at 0 °F (−18 °C). The rating is defined as being the current a lead-acid battery at that temperature can deliver for 30 seconds and still maintain at least 1.2 volts per cell (which equates to 7.2 volts for a 12-volt battery).
Cranking Amperes
Cranking amperes (CA), also sometimes referred to as marine cranking amperes (MCA), is the amount of current a battery can provide at 32 °F (0 °C). The rating is defined as the number of amperes a lead-acid battery at that temperature can deliver for 30 seconds and still maintain at least 1.2 volts per cell (which equates to 7.2 volts for a 12 volt battery).
Battery Technologies
The type of battery that your jump starter has can determine how well it will perform for you, this is because different battery technologies have different properties like how they deliver power, how fast they can be charged and when charged how long they can hold their charge.
The 3 main types of battery technology used are Lead Acid, AGM and Lithium Ion. Lithium Ion batteries hold there charge for longer, followed by AGM batteries and then Lead Acid. Charging times are also shorter for Lithium Ion followed by AGM and them Lead Acid, but lead acid batteries are more tolerant of over charging than AGM and lithium Ion can over heat and catch fire.
Weighing the pro's and cons of each battery technology is a definite must when considering which jump starter is best for you.
Cold Weather
When considering what type of jump starter you may like you should keep in mind cold weather and how it can affect the batteries performance, a lead-acid battery can lose more than 50% of its cold cranking amps, so if you live in a climate where the weather in winter drops below 0 °F (−18 °C) and you are planning on storing your jump starter in the trunk of your car, then you may want to increase to the next size jump starter.
Lithium-ion batteries have become common place in jump starters because they can store a lot of energy, but when temps fall below freezing, the batteries performance declines, and when conditions are cold enough, the batteries can fail to transfer any charge at all, so if your winters are snowy a lithium ion battery powered jump starter may not be the best choice for you.
Making A Decision.
Now that we have an understanding as to what all of the amp values mean on our jump starter we can start to put the pieces together. If you were able to find a CCA value on your car battery then this should be the minimum value you should be looking for when you choose your jump starter. If you didn’t find a CCA value then the following list can be used as a general guide based on the size of your engine, and what the power requirement are to start the engine.
- 4 cylinder gasoline engine 160 amps
- 4 cylinder diesel engine 350 amps
- 6 cylinder gasoline 210 amps
- 6 cylinder diesel engine 450 amps
- 8 cylinder gasoline engine 250 amps
- 8 cylinder Diesel engine 650 amps
What Next.
If you liked this article you may like to also read some of our other articles? We have several articles such as Why bother with a Jump Starter or What Features Must A Portable Jump Starter Have.
You may now feel like you would like to jump into the deep end and look at some Jump Starters. our Jump Starter page is categorized into different types of jump starters making it easy to check out the different types of Jump Starters available.