Technology behind the small jump-starters for cars?

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Discussion Overview

The discussion centers on the technology behind small jump-starters for cars, exploring various types of power sources such as batteries, capacitors, and fuel cells. Participants share insights on the effectiveness and limitations of different technologies in various scenarios, including cold weather conditions and the size of engines being started.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested

Main Points Raised

  • Some participants note that lithium-ion batteries are commonly used in modern jump starters, highlighting their compact size compared to lead-acid batteries.
  • Others propose that capacitors could also be a viable technology for jump starters, with some claiming they work well for short cranking durations.
  • A participant mentions that while capacitor-based boosters are effective for brief starts, longer cranking times may require larger batteries, such as motorcycle-sized lead-acid batteries.
  • Concerns are raised about the effectiveness of electric starters in extreme cold, suggesting that alternative methods, like pilot engines, may be necessary for reliable starting.
  • Some participants discuss the practical use of portable jump starters, noting that they can provide multiple jump starts without needing to be recharged frequently in warm climates.
  • There is mention of variability in user experiences with jump starters, indicating that factors like battery condition and connection issues can affect performance.
  • A participant shares a personal experience with a lithium jump starter that successfully cold-started a diesel engine, emphasizing its compact design and USB charging capability.
  • One participant humorously points out that user error, such as forgetting to charge the jump starter, can lead to issues in emergency situations.

Areas of Agreement / Disagreement

Participants express a range of views on the effectiveness of different jump starter technologies, with no clear consensus on the best option. Discussions about the limitations of electric starters in cold weather and the practicality of various battery types indicate ongoing debate.

Contextual Notes

Limitations include the dependence on specific conditions such as temperature and engine size, as well as the variability in user experiences and the potential for user error affecting the perceived effectiveness of jump starters.

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TL;DR
What's the technology used by the small devices that can jump start cars? Is it batteries? - capacitors?
What's the technology used by the small devices that can jump start cars? Is it batteries? - capacitors? Fuel cells?
 
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Stephen Tashi said:
What's the technology used by the small devices that can jump start cars? Is it capacitors?
Could be capacitors, they seem to be gaining popularity. . . 🤔

Super capacitor jump starter - YouTube

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I have seen demos of capacitor based start boosters. They work great if you only need 1-2 seconds of cranking.

If you need 1 minute of cranking, portable boosters with motorcycle size lead acid batteries are good.

If you need 5-10 minutes of cranking (think -40 degrees outside temperature and non-computer carbureted gasoline engines) then a large car/truck battery will barely do it.
 
anorlunda said:
If you need 5-10 minutes of cranking (think -40 degrees outside temperature and non-computer carbureted gasoline engines) then a large car/truck battery will barely do it.
Those electric starters are not all they are cranked up to be.
If the engine is big and the weather is really cold you need a pilot engine. That has magneto ignition, started with a pull cord, it then burns maybe half a gallon of fuel while heating and circulating the shared oil and coolant of the main diesel engine. You have time for breakfast, then you engage the clutch to start the main.
Not the sort of thing you drive around the corner to the shop, when you have a bicycle.
I see no future for this newfangled boosted electrickery stuff.
 
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Portable jump starters tend to have AGM/gel batteries inside, but more recent ones, like these: https://no.co/products/power/jumpstarters
...have lithium batteries. They tend to have reverse polarity and anti-spark protection. Reviews vary widely, from the best thing the user has ever bought, to totally useless. The variation may be due in part to the operator. For example, if your problem is a corroded engine Earth strap, and you connect the jump starter directly to the battery, it will suffer the same voltage drop and appear useless.

Mains-powered charger/booster units have the ability to start even large tractor engines on their own.
 
Stephen Tashi said:
Summary:: What's the technology used by the small devices that can jump start cars? Is it batteries? - capacitors?

What's the technology used by the small devices that can jump start cars? Is it batteries? - capacitors? Fuel cells?
I have one using a tiny Lithium battery and it works very well. It is capable of cold starting a 3L Diesel engine, and amazingly, is charged up using a USB socket. It fits into a small glove compartment and can deliver 600 Amps.
 
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One problem with these emergency jump starters comes with the user :rolleyes: - they forget to keep it charged.
 
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