Booster packs, any recommendations?

[Pillock]

Keep up at the back, I already explained it once.

 

WITCHCRAFT.

[tommotech]

I was going to say get the best you can afford and keep on top of charging it, letting them go flat with no use will bugger them up. Then I saw that little box of 'WITCHCRAFT' and suddenly want one too.

[Dead_E23]

It's because they have Lithium Ion batteries inside, which can deliver a lot of current for the size of them. They need external circuitry to prevent them overheating/overcharging/delivering too much current etc, and when it's left out to save a few Yuan they become prone to sudden Hoverboard-style pyrotechnics.

 

Anyway, whatever - phones and hybrid cars are full of the same type of battery and you don't often hear stories of them bursting into flames, so they must be fundamentally ok.

 

I reckon this alluringly cheap 600 amp jobbie might be just the thing for starting scruffy 200 Tdi Defenders that don't get enough use. Tempted.

[SiC]

As another hobby of mine, I have some of these:

 

This one in particular is powered fully electrically, at full bore shes pulling 4kw (5.3bhp) continuously for 5minutes. Running at 100A+ from a 2x5cell packs. If the cells were wired as 12v output, it'd be putting out 300A. The packs only get mildly warm too. Packs cost less than £30.

 

We've been doing this stuff in RC for years! My setup is no where near the bleeding edge either, all done with regular cheap Chinese gear.

 

So yeah, nothing particularly high end or special about those starter packs. Being lipo wouldn't leave them anywhere that gets hot though... I.e. in the boot of a car.

[Pillock]

I think the bit that confuses me is that the battery terminals are thick chunky bits of cable, yet you're connecting some proper flimsy bits and they don't melt.

I've tried jumping a 2.0 Golf from some cheapy jump leads before and the cable got really hot when I was cranking, yet they must have been 4x the cross section of the ones that come with the little packs.

[SiC]

I think the bit that confuses me is that the battery terminals are thick chunky bits of cable, yet you're connecting some proper flimsy bits and they don't melt.

I've tried jumping a 2.0 Golf from some cheapy jump leads before and the cable got really hot when I was cranking, yet they must have been 4x the cross section of the ones that come with the little packs.

I suspect they've cheaped out as copper is the expensive bit. The internal resistance is extremely low on lipos and I reckon what's happening is that when you connect them, they very quickly get some charge into the lead acid battery. This gives some additional buffer in getting it turned over.

[jonny69]

That Clarke Jump Start 4000 is what you want - save up the other £30 and your starting woes are basically over. Mine is 7 years old this year, I've never looked after it and it still always works whenever I need it. Really good bit of kit.

[jonny69]

It would start my 4 litre flathead V8 from completely flat, just connect and crank. It also spent around 3 months connected to the dead battery in SWMBO's Scenic which was in a properly awkward place. I just clamped it on and used it like normal.

[Jim Bell]

 

Xmas is pretty badass. Thanks to the shitter who reviewed these bad boys.

[Cavcraft]

I don't want it if it comes with Giant Haystacks

[Felly Magic]

I suspect that those ultra small chargers contain quite a few capacitors to give the welly needed, i've seen via Photon's channel what a wallop capacitors can give

[cobblers]

I think the bit that confuses me is that the battery terminals are thick chunky bits of cable, yet you're connecting some proper flimsy bits and they don't melt.

I've tried jumping a 2.0 Golf from some cheapy jump leads before and the cable got really hot when I was cranking, yet they must have been 4x the cross section of the ones that come with the little packs.

The wires do get fairly warm, but the voltage drop isn't significant because the wires are so short.

[PhillipM]

I suspect that those ultra small chargers contain quite a few capacitors to give the welly needed, i've seen via Photon's channel what a wallop capacitors can give

 

Nah, just high-C lithium cells, 25C cells are cheap these days, and 40-50C discharge aren't too much more either.

[dollywobbler]

It does seem very tempting magic. Think to remember though is imagine a Nissan LEAF and the size of the battery pack if it still used Lead Acid. I bet you'd need a bloody trailer to have the same power output.

[PhillipM]

Our race batteries (also lithium) weigh 1.9kg, are about the size of a motorcycle battery and will crank the car over no problem from cold even with a high compression engine and a 'charger to spin over, even twin 16 inch fans and electric PAS pump to run all day.

The best bit about them is they lose very little charge too so even parked up in winter it will fire up 2 months later.

[Dippy]

Xmas is pretty badass. Thanks to the shitter who reviewed these bad boys.

Bought one of these a few months back and managed to start a Chrysler 6.3 L V8 twice when alternator packed in and wouldn't have got home without it. Actually bought it in case I forgot to turn of lights in 2.3L Victor and was amazed what a small box could do.

[Lacquer Peel]

Is it this one?

http://www.workshopplus.co.uk/collections/car-jump-starters/products/smart-box

[Jim Bell]

Is it this one?

http://www.workshopplus.co.uk/collections/car-jump-starters/products/smart-box

Indeed.

[Lord Sterling]

I saw one of those "laptop battery" sized jump starters that a car trader mate was using. Couldn't believe it but it worked. He was quoting prices of around £200 or thereabouts. Though if they are at £80 or so it'd certainly be a great bit of investment.

[Dippy]

Is it this one?

http://www.workshopplus.co.uk/collections/car-jump-starters/products/smart-box

Yep it's fantasic and saved me from going home on a recovery truck.

[Tamworthbay]

I can't believe those little tiny boxes can put out enough power to start a VM Diesel or something, but the only other explanation is there's hundreds of people in on a joke because there's a lot of good reviews.

Also, can charge my phone 6 times, and power a laptop for three hours or something daft.

WITCHCRAFT.

my best mate is an electronics engineer and was more than a little sceptical when his other half bought one. But it started his 924 with a knackered battery that hadn't run for a month. We were both amazed. Personally I keep an agm red top and jump leads handy, it's half the weight of a lead acid battery and will hold its charge for months and months.

[Keymaster]

That phototonicinduction geezer on YouTube tested a Carpow one or something and it started a Merc V8 with the battery disconnected no bother. He seems pretty clued up and don't think he'd give a good review to something shite.

 

https://youtu.be/I_pzljtJapE

As a recipient of one of these things for Christmas, this is good news!

[HH-R]

I was fully expecting it to fall straight on its arse in the Photonic video, but it's very impressive!

[andrew e]

I'm tempted to leave the mother-in-laws identical (Red) Picanto lights on just to replicate this:

 

1:50 is my favourite bit:

 

[DeeJay]

Would it be possible to use one of those little jump packs as a replacement battery?

(I hate playing with electricity, I always think it's job is to kill me with extreme pain) 

[daveb47]

Recieved mine at 7:40 this morning.

On charge at moment from usb on pc.

[skattrd]

Recieved mine at 7:40 this morning.

On charge at moment from usb on pc.

 

I'd expect that charging 16000 mAh or whatever through a USB port will take quite some time. I'd charge by the mains and save USB charging for top-ups or emergencies.

[cobblers]

Yeah. Mine takes 6 hours to charge at 15v 1A. On a PC USB port it would take a 36hours +

 

 

Would it be possible to use one of those little jump packs as a replacement battery?

 

 

Yes and no.

The trade off with Lithium Ion cells is that while they are very powerful for their size/weight, the voltage on them needs to be kept within a tight margin (between 3v and 4.2v per cell).

If you stray outside this range, there's a good chance the battery will be seriously damaged. A damaged battery will often catch fire spectacularly when you charge it.

 

These boost packs have three cells in series to give approx 12v when fully charged, but your car alternator will try and push this up to 14.8v when running. This will cause each cell to eventually rise to 4.9v and the thing will just go up in flames.

To stop this happening, there's always a big lump in the middle positive lead out of the jump packs - this is a diode (usually several very beefy ones in parallel actually) that stops reverse flow of current back into the unit, so that t doesn't catch light once the car starts.

These diodes are usually quite a weak spot and are being run beyond their spec, hence they put then in the easily replaceable leads rather than having them inside the unit.

 

 

Starting a car without a battery at all with one of these probably won't damage the pack, but it probably won't do the car any favours as there's nowhere for the alternator to sink any spikes and there's a good chance the output voltage will oscillate wildly and you could potentially damage something expensive and electrical such as your ECU or stereo or whatever.

 

 

You can get "proper" lithium batteries for vehicles but I have no idea how these work.

[dieselnutjob]

I used a neighbours booster thing to start my 607 a couple of weeks ago, and I won't be doing it again on a vehicle that contains computers.  It only just started and various warning lights came on as the ECUs got upset about the lack of volts.  Basically the power it was supplying was really marginal, and on any French car since the 406 this is a really bad idea because you risk corruption of the BSI, which effectively bricks the car.

 

I know that Rover 75s have similar issues and so I will assume that SWMBOs Freelander will have as well as they are more or less a 4x4 75.

 

I will only use another vehicle with the engine running and some good thick jump cables on these cars.

 

I know that this might be a bit neurotic but 607s get scrapped because this kind of thing.

 

If things get really desperate I would boost the 604 first (no computers) and then jump the others from that.

[Pillock]

Cheers Cobblers, my next question was going to be "what's in that big lump on the positive lead?"