Jump start unit as emergency power source

[PhilC]

Have been considering options to set up an emergency power source for radio transmission and possibly lights, bilge pump etc in case my main battery bank (which is under the saloon sole) gets flooded. Obviously could also double as an emergency supply for engine starting or starting other people's engines in it's originally intended mode.

Have been looking at a lithium option like this: https://www.tridon.com.au/products/M...446409/MA35000

Some have a 12v supply (cigarette lighter type) ?10A? but not sure if this would generate sufficient current to transmit on the HF radio so expecting to have to connect to the jumper leads which likely have some BMS controlling the high current for starting?

Interested to know if anyone has tried this before?

[jmh2002]

Ultimately it's just a battery so yes in theory it can work.

You can also search for 'Portable Power Station' to see some other different options.

[PhilC]

Thanks for response, the portable power option would tick some of the boxes but I'm not aware of any that are also suitable for jump starting a diesel?

[TheOffice]

We carry a portable jump starter bought on Amazon - a GoLoo? Starts a V8 car, a boat etc. Not sure about how long it would power an SSB.

[GordMay]

The Matson 12/24V Lithium Jump Starter [35000MA] has a
35,000mAh [35 Ampere-hours] internal battery capacity, which will [likely] power 10A, for < 1.5 Hours.
A rule of thumb is for a 100 watt output transceiver use at least a 20 amp power supply. A50 watt transceiver can usually be run on a 10 amp supply.

[Hermia II]

If you want something robust to sustain you in an emergency, maybe after a bolt of thunder, keep it simple and use normal Lead Acid batteries. Check out the new Lead Carbon Batteries at Victronenergy.com

[ozdigennaro]

If you want to transmit HF at 100 watts ("barefooot"), the radio will draw 20-25 amps.
the cigar lighter connector will melt down. The best solution, inexpensive and reliable, is Anderson PowerWerx connectors. Way better than jumpers. Easy to install.

If you transmit HF at lower output wattage, you'll required proportionately less power, of course. But if you're in an emergency, you'll probably want 100 watts output.
Emergency communication groups all over the place use PowerWerx as their standard.

[Mike Banks]

Yes--I always had a jump-starter as an emergency radio battery. It was the cheapest option available, but the ones I used were not lithium ion but sealed lead acid self-catalysing low maintenance ones. They are fine emergency radio batteries, but not much use for starting a diesel engine although I have started cars with them. The ones I had had also a USB connection and would pump tyres as well and one could charge a flat phone from it too.

[Jammer]

Many if not most "jump start units" are designed and manufactured to be as inexpensive as possible; most now use lithium batteries. I don't trust them.

[Sternwake]

I have a 3 year old 35US$ Ub12180, a chinese AGM battery.

When i first got it it by itself had enough CCA( barely) to start a overnight cold 5.2 liter v8 engine in warm ambient temperatures

recently I used it to power, through an 12vdc 800 watt MSW 115vac inverter,

A 4.5 amp 'buckethead' shopvac, for several minutes
A 9 amp leaf blower, on the low setting.

The buckethead is drawing about 32 amps from the batteryt
The leafblower was drawing ~38 amps.

I was able to use both, for as long as needed, several minutes, and the inverter starts alarming at 10.49v but does not cut out until lower.

I use 45 amp Anderson powerpoles on battery and inverter and 8awg.

I've exceeded their 45 amp rating, many times, and some of those times were about 60 amps for 15+ minutes, but I stuff 8awg into them, they say 10 awg max.

The Ub12220 is a 22Ah AGM and the same exact size as the Ub12180 @ 18AH. The Ub12220 weighs about 3 lbs more.

If I had deeper pockets I'd get one of Odyssey Agms powersports batteries, but honestly these cheap chinese AGMS have met my requirements as a portable 12v power source.

The 3 year old 18 ah one has been a bit weird in that when charging, watching amps taper at 14.5v, they will often stop tapering and start rising in the 0.3 range. I have to let it sit, rest and start applying 14.5v again, and then amps they might taper to 0.09 before starting to rise.

The 2 year old Ub12220 just tapers to near zero at 14.5v and amps never start rising again.

With the automotive lithium jump packs, often their capacity is marketed in mAH, at 5 volts DC, or perhaps the lithium cell capacity at 3.4 or 3.7 volts.

The Lithium jumperpacks have impressive engine starting abilities, but their capacity, in terms of powering 12v items for extended periods, will likely prove disappointing.

[ShawnMack]

Do be aware some "smart" jump-packs only supply power for X number of seconds. I have 3 different packs. The two lithium packs stay on for 30 seconds and 45 seconds respectively. The third is an old lead-acid one from a discount tools store and stays on as long as the switch is on and there is juice in the internal battery.

This Could be a deal-breaker for anything other than an emergency "jump" to start an engine.