Technology behind the small jump-starters for cars?

[Stephen Tashi]

TL;DR 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?

 

[Baluncore]

Jump starters using lithium-ion batteries began appearing on the market in 2013. Most lithium jump starter brands use a high discharge lithium polymer or lithium-ion battery. Lithium jump starters are extremely compact and lightweight, as much as 90% smaller than lead-acid equivalents.

https://en.wikipedia.org/wiki/Jump_start_(vehicle)#Battery_booster_and_jump_starter

 

[OCR]

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

.

 

[anorlunda]

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.

 

[Baluncore]

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.

 

[Stephen Tashi]

The local road service companies used by AAA now send a person in a small car instead of a tow-truck for jump starts and flat tires. The last road service guy I watched carried one of these: https://www.harborfreight.com/autom...table-power-pack-with-jump-starter-62306.html He said he could get about 40 jump starts without recharging it. (This is in a warm climate.)

 

[Guineafowl]

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.

 

[tech99]

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.

 

[256bits]

One problem with these emergency jump starters comes with the user - they forget to keep it charged.