Portable battery jumper question

orbital

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My nephew is getting his engineering degree from UW Madison, as a gift, picked up a portable battery jumper unit for his fishing boat.
It arrived & I took a good look at it for build quality ect..
Built well & has various outputs, so I checked the voltage on the clamps, they read 16V (also, that's not fully 100% charged)
Obviously a four cell setup,, I thought, isn't that high for voltage, or an I missing something:thinking:

Even 15V off an alternator for car is considered HIGH,, so should I be worried about this at 16+V,, will it step down in voltage? hmm


Just don't want him to fry his boat motor electrics.

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personally, I have a 3S LiPo that works great, but requires a special charger.. a 3S is 12.6V fully charged
 
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I understand the immediate answer could be 'if electronics were blowing, it would be taken off market'

thing is, being an outboard boat motor, which isn't quite as robust as a car system,
car system can absorb more voltage.


It's this unit: https://www.amazon.com/AVAPOW-Starter-18000mAh
 
I think that likely fully charged it won't gain more than about 0.08v. Like raggie said these devices are for helping to start vehicles that have batteries in them. The battery in the vehicle will put a load on them and immediately drop the voltage to somewhere between the two voltages of the two batteries. Being that normal vehicle batteries are larger and have mostly 12.6v charged, and 11v discharged you will probably see the voltage drop on the battery pack to about 14.5v or less which is IMO safe for most devices designed for 12v systems I think.
 
a temp compensated regulator can reach and even exceed 16v on a very cold day.
nothing to be concerned with.
it will force a bit of charge into a good but discharged battery.
this may make it work better than a 3s.
 
I use mine routinely to jump small motorcycles (sub 200cc), lawn mowers, etc. with much smaller batteries than my car. May not put your mind at ease, but I've never had a problem with anything I've used it on.
 
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