Tiny Jump box

island808 · Post by **island808** » Tue Aug 20, 2013 2:23 pm

My Suzuki does a 4 second crank with one flick of the key. It is new and kicks right over cold. I tried it again... Cold engine... Not run In 48 hours. unhooked the battery and jumped it straight to the engine. Boom... Started right up.

No, you're not cranking water out of your engine with it... But if you dozed off listening to the radio with an inverter and awoke to the beep of the low power alarm, bam.

It doesn't weigh much at all. The documentation claims up to 400 amps. (220 to 450 I think) There has to be some high output capacitor stuff going on. Lithium battery couldn't discharge that fast could it? Too much internal resistance? No visible screws on it and the rubber seems to be glued on. No easy disassembly that I see so far.

Tried to take it apart... No joy.
It weighs 410 grams (14.5 ish oz)

RobertB · Post by **RobertB** » Tue Aug 20, 2013 2:47 pm

I assume lithium ion because that is about the most power to weight of commercially available batteries today. Do not know enough on the discharge rate and how it is accomplished.

Max Entropy · Post by **Max Entropy** » Tue Aug 20, 2013 3:55 pm

seahouse wrote:Hey Nick!

I can't see that you would get that capacity in real life...

Couldn't agree more - probably lucky to get 50%

seahouse wrote:ps. you slipped a decimal point over, =0.01875 hrs, but recovered it in the minutes conversion- nice recovery!

Just checking to see if you're awake...

- Nick

island808 · Post by **island808** » Tue Aug 20, 2013 4:20 pm

So the other night i plugged my 100% dead ipad into it, and proceeded to fall asleep watching netflix.

I woke up in the morning, the ipad was at 90% charge and battery pack was dead. Figure i was using the ipad for maybe 40 minutes before it went to sleep. So maybe the discharge capacity. For one of these apprx equal to an ipad2

Next time im at the boat ill try to get some videos of it starting, see how many starts i can get out of it.

Speaking of which... Dual bluetooth gps receiver, ipad (wifi only) and isailor makes for a pretty awesome chart-plotter on the cheap (assuming ipad ownership). Always have 3-4 electronic chart plotters, and a chart book onboard. Future is now... 80 s me would be mind blown

mastreb · Post by **mastreb** » Tue Aug 20, 2013 4:51 pm

Probably this is 4 Li-ion cells in series. Li-Ion can discharge at extremely high rates: 200A is easily achieved by just about any Li-Ion cell. The device isn't large enough to have a substantial capacitor in it. The basic Li-Ion cell has a natural voltage of 3.6v and a typical power dissipation of over 1000 amps before unsafe temps are reached, so this is likely a bank of 4 cells.

WASP18 · Post by **WASP18** » Tue Aug 20, 2013 5:24 pm

I just bought this jump starter today for $48.88. Apparently it's a fast seller. Had to visit TWO Walmarts, and bought the last one.
Schumacher model XP 500 with an on/off switch. Stay away from the XP 400 for ten bucks less. It doesn't have an on/off switch!
http://www.walmart.com/ip/15140203?wmls ... 90&veh=sem

seahouse · Post by **seahouse** » Tue Aug 20, 2013 9:05 pm

Yup – my guess would be Li-ion too, (as opposed to NiMH) as being inside these puppies, but could be either one, they both can supply the high-amp draw needed. (Like hybrid cars, that use both, do).

Catigale · Post by **Catigale** » Thu Aug 22, 2013 4:27 am

mastreb wrote:Probably this is 4 Li-ion cells in series. Li-Ion can discharge at extremely high rates: 200A is easily achieved by just about any Li-Ion cell. The device isn't large enough to have a substantial capacitor in it. The basic Li-Ion cell has a natural voltage of 3.6v and a typical power dissipation of over 1000 amps before unsafe temps are reached, so this is likely a bank of 4 cells.

Even higher rates when they are airborne, but then they catch on fire.....

Post by **Russ** » Thu Aug 22, 2013 8:36 am

Catigale wrote:
mastreb wrote:Probably this is 4 Li-ion cells in series. Li-Ion can discharge at extremely high rates: 200A is easily achieved by just about any Li-Ion cell. The device isn't large enough to have a substantial capacitor in it. The basic Li-Ion cell has a natural voltage of 3.6v and a typical power dissipation of over 1000 amps before unsafe temps are reached, so this is likely a bank of 4 cells.
Even higher rates when they are airborne, but then they catch on fire.....

I wonder if you can order one of these shipped next day air?

Crikey · Post by **Crikey** » Thu Aug 22, 2013 1:30 pm

So, at $50 per - for Lithium ion - would that be cost/capacity competitive with a deep cycle marine battery? It sure weighs a heck of a lot less!

Ross

RobertB · Post by **RobertB** » Thu Aug 22, 2013 1:32 pm

I am going to guess that that $50 battery is about half the capacity of my laptop computer battery. The reason it can start an engine is that it can discharge quickly - but not for long.

seahouse · Post by **seahouse** » Thu Aug 22, 2013 2:39 pm

Hey Crikey! 'you home yet, or continuing your journey?

The hard science is that no technology has yet been able to surpass the value of the flooded lead acid battery for cost per, over their lifetime. They remain the king of the hill in bang for the buck. But advancements are being made all the time.

Technologies on the market now, other than FLA, do have advantages, other than low cost and dependability over their lifetime. Such, as you mention, weight, but you do pay the price for those other advantages, when and if you need them.

Hey RobertB - Depending on how old your laptop is, the battery in it could be the same technology (NiMH, or Li) as this product, but made up of several laptop batteries connected together to get the capacity it needs in the size of the package.

Believe it or not, the batteries in earlier (maybe some still today?) hybrid cars were actually stacks of laptop batteries wired together. (Why develop the same technology twice?)The size, shape and capacity could be adjusted to fit low in the vehicle, and conform to complicated profiles of the vehicle.

RobertB · Post by **RobertB** » Thu Aug 22, 2013 4:02 pm

seahouse wrote:Hey Crikey! 'you home yet, or continuing your journey?

The hard science is that no technology has yet been able to surpass the value of the flooded lead acid battery for cost per, over their lifetime. They remain the king of the hill in bang for the buck. But advancements are being made all the time.

Technologies on the market now, other than FLA, do have advantages, other than low cost and dependability over their lifetime. Such, as you mention, weight, but you do pay the price for those other advantages, when and if you need them.

Hey RobertB - Depending on how old your laptop is, the battery in it could be the same technology (NiMH, or Li) as this product, but made up of several laptop batteries connected together to get the capacity it needs in the size of the package.

Believe it or not, the batteries in earlier (maybe some still today?) hybrid cars were actually stacks of laptop batteries wired together. (Why develop the same technology twice?)The size, shape and capacity could be adjusted to fit low in the vehicle, and conform to complicated profiles of the vehicle.

Yes professor - I know this.

seahouse · Post by **seahouse** » Thu Aug 22, 2013 7:38 pm

Great; your sincerity and valuable endorsement are very much appreciated!

island808 · Post by **island808** » Thu Aug 22, 2013 8:00 pm

Looks like they got more in stock. No more ships in 30 days bs.

MacGregorSailors.com

MacGregorSailors.com

Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box

Re: Tiny Jump box