Smart tech jump starter for cars - Page 1
Forum section: electronics / general

author: ptricks
author_rank: Frequent Contributor
timestamp: June 13, 2019, 12:02:58 pm
content: Watching tv this morning , first thing I see when I turn it on is an infomercial for smart tech jump starters for cars. I was about to turn it when they show some guy with a meter and a car battery saying, this battery only has 8 amps , the meter is set to volts and it is one of those $5 metersHe then proceeds to hook up the gadget they are selling and shows it starting the vehicle not once , but over 50 times !But wait, there's more !It also charges all your USB devices, powers your laptop, has a built in light, and uses their proprietary lithium ion technology with a powerful 12A of battery power and up to 500A of on demand power, yours for just 4 payments of $39.95.Sometimes I hate myself for not taking advantage of all the suckers out there.Their commercial , the guy with the meter is at 21:00.

author: Muttley Snickers
author_rank: Unknown
timestamp: June 13, 2019, 12:31:14 pm
content: I nearly forgot again, thanks for the reminder to put my battery on charge first thing tomorrow morning. I hadn't used the Toyota for a few weeks and had an important scan scheduled at the hospital yesterday morning and almost missed it due to a flat battery.I was already running late and the last thing I expected was the truck not turning over, fortunately I had plenty of charged 7.2 amp SLA batteries in the garage so I grabbed one of those along with some jumper cables and it was just enough juice to get me going.

author: mzzj
author_rank: Super Contributor
timestamp: June 13, 2019, 12:53:29 pm
content: Quote from: ptricks on June 13, 2019, 12:02:58 pmSo what? since when US "tv shop" advertisements would have been hugely accurate on technical things?Mostly the boosters/jump starters work as claimed, ie charges USB devices, powers your laptop, has a built in light and starts your car multiple times. (as long as its not 6.2L diesel with dead glow plugs in the middle of the winter at -30c)

author: GlennSprigg
author_rank: Super Contributor
timestamp: June 13, 2019, 12:56:00 pm
content: I'll probably cop some 'flak' here, but that's why my name is 'glennsprigg' hahaI hate the fact that so many people believe that (heaven forbid!!) you DARE to Jump-Startamoderncar, as you will result in a computerized 'melt-down', and start a 3rd World War !!Of COURSE there are Basics, that need to be considered, but beyond that, it's like old ladies hatingdaylight-savings times, as the extra 'daylight' fades their Curtains quicker !!!!!!I've been an Elect/Tech formanydecades, and I have NEVER had a problem. Apart from that though,I've spoken to MANY roadside RAA techs, who 'jump-start' countless cars EVERY day, with no problemsALL they say, is to NOT have the engine running on the Donor vehicle, & connect the Earth first.....Not rocket science!! Oh... P.S... I probably wouldn't rely on my iPhone backup battery to start a Mack truck.

author: ataradov
author_rank: Super Contributor
timestamp: June 13, 2019, 06:09:48 pm
content: While ad is obviously bull, I do have one of those starter things (not as "advanced"). And it does work as advertised. I had to use it a couple times, and I would say is worth the investment. I've got it for something like $60 from Amazon.

author: Benta
author_rank: Super Contributor
timestamp: June 13, 2019, 07:34:43 pm
content: Quote from: ataradov on June 13, 2019, 06:09:48 pmTrue, but they're not the size of a cell phone, more like a laptop case. And won't support 50x cranking.

author: Benta
author_rank: Super Contributor
timestamp: June 13, 2019, 07:43:18 pm
content: Quote from: GlennSprigg on June 13, 2019, 12:56:00 pmI mostly agree with your post, except: always connect plus first (and disconnect last).

author: ataradov
author_rank: Super Contributor
timestamp: June 13, 2019, 08:08:05 pm
content: Quote from: Benta on June 13, 2019, 07:34:43 pmHere is exact one I havehttps://www.amazon.com/gp/product/B01MY9FZM4/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1The unit itself is 7.24 x 3.46 x 1.5 in, which area-wise may be close to some large phones, but not the 1.5" thickness, of course.It is advertised as "it’s able to jump start flat batteries up to 30 times on a single charge". I guess it would depend on what "flat" is, but my guess it is good for 10 times or so, it is a pretty beefy battery.

author: mzzj
author_rank: Super Contributor
timestamp: June 13, 2019, 08:11:15 pm
content: Quote from: Benta on June 13, 2019, 07:34:43 pmYou have either really small cell phones or tiny laptopsNobody said how long each of those 50x crankings takes so.. typical modern car with EFI starts in less than second.Maybe 200 amps for small-ish gasoline engine in summer temps = 1*50*200=2.7Ah capacity needed, about what those small jump starters have.Product shown in first post is advertised as 12Ah, probably three 4Ah li-ion batteries in series =12Ah marketing capacity.200 amps out of 4Ah li-po battery is nothing new anymore, RC plane folks run even at higher currents.

author: discomike
author_rank: Contributor
timestamp: June 13, 2019, 10:09:21 pm
content: With the engine warm starting it does not require much energy, I have started/stopped a car more then 300 times in a row on the normal battery with plenty capacity left... It took about 30-40 minutes of turning it on/off again

author: amyk
author_rank: Super Contributor
timestamp: June 14, 2019, 01:45:09 am
content: 500A peak current from a tiny lipo is definitely possible, but not something you'd want to sustain for any length of time: