Powerpack

[Tomax]

Have just met a German couple travelling Australia in their 2.9 diesel Merc G Wagon - very experienced and well prepared world travellers who have previously travelled here, including the southern half of the CSR. There is insufficient room for a dual battery set-up in their wagon (without significant re-positioning of components) and they are wondering about a Powerpack (or equivalent) as a back-up in the event of battery failure. I've had no experience with these and said I would ask for advice on this forum. They simply want something that will comfortably start their Merc should their battery fail, so I'd welcome any advice from those who have used these on the best brand, appropriate size, cost, best source, advantages/disadvantages, etc.
Thanks

[GQANDGU]

I bought one for my last vehicle, a V8 Grand JEEP, and still have it 5 years later. Cost about $380 from memory. Used a couple of times to start the V8 without problem and now carry it in the boat at all times as an emergency starter.

Mine is an 'OUTBACK POWER PACK'. Can be charged from a standard 240V charger (WITH AUTO CUT-OUT), or from 12V power plug while travelling. Will run the Fridge for almost 48 hours without recharging if needed.

There are bigger, more powerful (& more expensive) on the market, but it is a balance of Weight and Capacity when travelling.

[Buick]

Here are some, you can get them from most 4WD and camping shops.

http://www.bitdistribution.com.au/?stg=240
http://www.kookaburragas.com.au/camping_power.htm