Lithium jump starters

I would also endorse the GB70 , have investigated a few units and although pricy ($300) this one is well suited to the task , the bigger versions like GB150 are also great but an overkill for most of us.

Good point re the fridge.
Hadn't considered that in my excuse list for buying one.

have you tried it on a 4lt diesel that has to circle glow plugs 1st
on a cold start I doubt it
mechpete

Hi Bill. Have you ever used that Itech900A in anger. I have and didnt get a peep out of it, and none either from Itech. Very disappointed that I actually bought 2. Neither start a 3l diesel. I think I read that it wont start if battery is less than 10.5 v, not sure, but if that's the case, bloody hopeless.

If you intend to rely on it for remote travel, try it first somewhere that you have backup. Same suggestion no matter which model of these you have.

.
Hi Neihoh, (how on earth do I pronounce that?) lol

I have no real experience with iTechworld's or any other Lithium jumpstarter, but I would expect much the same from any of them.

iTechworld put up a smart website but I was dismayed at their pop-up that every 15 seconds tells me that "Someone in 'Gondwanaland' just bought a product". Particularly when they say that it was "purchased in their shop" at 6:00am on a Saturday morning!!!!!

I get so fed up with the wiles of salesmen pushing their products. If their sales expressions are so dishonest, what is the quality of their products?

Am with you re the pop ups Allan. Actually a typo in the screen name. Hope I didnt have similar brain fade when I did up my wheel nuts last time.??

As soon as I saw the nupnups head I turned it off.

.
Yep, John Cadogan it is........

If you cannot be convincing being rational..... try being potty-mouthed!

Not really interested in what you did, BigFish .. it was intended for Garny.
I am sure he can speak for himself.
OBJ

Yes he does go on a bit dramtically does he not? However, for once I agree with what he has to say this time. The lithium power packs work a bit the same way. They both do not store much energy but they are capable of providing a short shot of high power.

And up your s too obj

Old Chinese proverb BigFish ..

If you feel insignificant, you are....

Happy days and safe travels.

OBJ (with capitals.).

Dont feel too bad..your insignificance isn't worth worrying about.

Safe travels too.

Awwww come on fellas.

This isn’t the caravanners forum

Cheers Greg.

No it is the silly old farts forum.

" No it is the silly old farts forum. "

And getting worse by the day !!

I resent that Garry. Don't deny it, just resent it. Anyway, it's good to have you and Gazz as contributors to the forum. :)
Dave.

That might sound OK RMD but how are you going to impress people around the campfire at night without being up with the latest trend.
Dave.

Back when I got caught out with both starter batteries flat in the high country, I tried piggy backing the fridge battery and the camper battery. But both were deep cycle and didn't have the oomph to start a diesel V8.
Keith

I wonder how Molly Clark got on if she didn't have one of these in the Kingswood's glove box ??

Keith B2
Did you link the two aux batteries to the two (in parallel) main batteries and expect it to start? Two huge batteries will sink current into themselves and the available flow will most likely be absorbed with insufficient to start a larger engine. Unlinking one main battery would have been better. Better still, start off the two aux and then jump to the original batteries to begin charging them. Only need to run for a short time and the engine will then restart on the OE batteries as per normal.

The available current of a Lithium unit also has to run into the two OE mains and is being absorbed by them whilst trying to start the engine. Taking as many batteries out of circuit as is possible, to assist starting, is good when the chips are down.

Good advice RMD. Many thanks.

.
Not so sure that's right RMD.

The probability is that the "flat" batteries were sitting at about 11 volts and their internal resistance would be up a bit. Assuming that the "fridge battery" and "camper battery" were sitting on 12 volt (at no load) then the 1 volt differential between them and the cranker would induce little current flow from the donor batteries. It is more likely that the internal resistance of the donors was not low enough to provide starter current. It is also possible that the jumper leads, like most commercial ones, were not adequate. (or a combination of these)

As support to this I offer the experiences of the usual car-to-car jump-start where the donor battery is simply paralleled to the vehicle with the 'flat' battery and the start is usually successful.

If you have a shorted cell in a "dud" battery - caused by total plate collapse, or by debris building up on the bottom of the case until it reaches the plates and shorts them - then hooking up another battery to the dud battery will result in poor jump assistance, as the dud cell will short out a lot of the power.

In the old days, with individual capped cells, it was a simple test to see which cell was the dud, by hitting the starter and watching which cell spouted acid like a geyser!

However, with todays sealed and semi-sealed batteries, it's not so easy to find a shorted dud cell.
If you suspect the dud battery has a shorted cell, it's better to disconnect the dud battery completely, and hook up the jump battery only.

Cheers, Ron.

Allan B
Yes there are many if's, maybe's and possibles, most of which are not obvious at the time but need to be allowed for.

When considering starter currents, the modern vehicle draws less than starter currents in previous decades. The cables used to be thick on most vehicles, especially where the engine was bigger, now the cables are far thinner which indicates less starter current draw required. Therefore, jump starting from another source should be more easily achieved than before.

.
Ron,
The phenomenon of a "shorted cell" in a flooded lead-acid battery is rarely a bridging of a cell with a low resistance. It mostly occurs due to the shedding of plate material which progressively builds up and bridges the bottom of the plates. This forms a current path which discharges the cell but is not a high-current path. This degradation of the battery is usually accompanied by plate sulphation which causes increased resistance of all cells thus limiting high-current delivery.

In rare cases of separator failure, opposing plates may come into contact which will create a shorting current path of lower resistance. This usually occurs due to excessive heat or very high current flow. It is rare in modern batteries with improved plate separator material.

I won't attempt the mathematics of it but take my word for it..... paralleling a "flat battery" with well charged donor will not 'suck-the-guts' out of the donor. Little current will be absorbed by the flat battery compared to the demand of the starter motor. Inadequacies are more likely the condition of the donor battery and the jumper leads. The "fatness" of spark at the moment of jumper connection is an indication of current flow to the flat battery. I would assess it as being no more than 20A in most cases and usually less.

Disconnection of the flat battery during jump-starting can be achieved if done carefully but is rarely necessary and may be hazardous to the vehicle's electrical system especially in vehicles with electronic management. I have never found a need for it.

I have witnessed a lot of poor performances and failures of batteries but never the one you described of a "cell spouting acid like a geyser". Interesting!
Perhaps the most bizarre of my experiences was a 6V battery which incurred a totally open-circuit cell. I bridged the cell out with wire to produce a 4V battery and left it connected to the vehicle system while driving for several hours before replacement. It worked!

RMD,
Certainly, starter cables have become thinner, notably with the move from 6V to 12v systems. Improved starter motor design probably plays a part. But competitive economics has also reduced the copper in jumper cables which impedes the process.