Thread: What should I get as 2nd battery

Wouldn't it depend on how long your driving for as to how quick you need the battery to charge as to what type of battery you need?

Whatever you get make sure it is a sealed AGM type battery. Lead acid inside your vehicle cabin is dangerous and will void your insurance if you have an accident.

I have an Optima red top for starting and a Optima yellow top for aux battery. The yellow top runs my fridge for a couple of days no problems and the red top starts first time, every time.

Originally Posted by warren9981

Whatever you get make sure it is a sealed AGM type battery. Lead acid inside your vehicle cabin is dangerous and will void your insurance if you have an accident.

Hi Warren and that’s a bit of a myth, plus, all batteries, except lithiums, are lead acid batteries, including all AGMs.

All batteries are safe to use inside the cab of any vehicle.

The only requirement is that the battery, no matter what type of battery it is, it should be mounted inside a plastic battery box.

Next and this is just a suggestion, probably the best battery on the market is the Optima Yellow Top, BUT the further away you locate a Yellow top from the cranking battery, the less the advantage is for using a Yellow Top over any other battery.

A Yellow Top will still charge faster than a conventional battery, even at the end of a long run of 6B&S cable ( standard DBS Cable size ) but it will not charge as fast as when it is close to the cranking battery.

So combine the reduced recharging capability and the small size and the advantage is lost.

For less money you can fit a Remco, a very good battery, or for even less cost, you could fit an Allrounder.

In both cases you would have a larger capacity for a lot less expense.

Note, both of these batteries are Calcium/Calcium batteries and as such, you need to give them a BOOST cycle charge every month or so with a decent mains battery charger.

Now, just to throw a spanner in the works, if cost was not a limiting factor and it is for most people, but if you could justify the cost, two small Optima Yellow Tops and some decent cabling would give you the best deep cycle set up with a realistic battery capacity.

I have a 2nd Optima 55Ah battery under the bonnet with a dual battery relay. This is used as the back up for the winch. Because of volt drop issues with the fridge I fitted a 3rd battery in the rear in the cargo recess. 200Ah Deep Cycle
I believe it is sealed but if too high a charging current is used it is possible it will vent excess pressure. To increase the life do not discharge past 50%. I have 4mm cables running from the engine bay and blocking diodes so the 3rd battery will charge from the alternator but not supply anything but the fridge and inverter, no battery leads from front to back. I have changed all the plugs and sockets to Anderson type. I will be fitting a solar panel for extended camp trips.

[QUOTE=drivesafe;1868399]Hi Warren and that’s a bit of a myth, plus, all batteries, except lithiums, are lead acid batteries, including all AGMs.

All batteries are safe to use inside the cab of any vehicle.

The only requirement is that the battery, no matter what type of battery it is, it should be mounted inside a plastic battery box.

Just after clarification Drivesafe "after checking the Australian Government Website" http://www.infrastructure.gov.au/roa..._COP_sec_7.pdf

7.7.1 Batteries are to be secured and placed in a container suitable for the purpose of holding a battery. The battery must be positioned outside of the passenger compartment unless it is in an enclosure that is vented to the outside of the passenger compartment. A dry type battery may installed inside the passenger compartment.

Are the yellow tops and "AGM" batteries classed as dry cell or wet cell?

Hi Warren and sorry mate but there are more than two dozen “NEW” makes of vehicles that have the cranking battery fitted in the cab, or boot or some other compartment joining the cab of these vehicles, including VE Commodores.

The Commodore is a perfect example of how the law is interpreted.

The cranking battery is NOT a dry type but is fitted in the boot, which is not hermetically sealed from the cab and the later versions have no drain pipe so the battery is vented into the boot and CAB.

If the manufacturers can do it then there is no reason anybody else can’t.

Originally Posted by drivesafe

The cranking battery is NOT a dry type but is fitted in the boot, which is not hermetically sealed from the cab and the later versions have no drain pipe so the battery is vented into the boot and CAB.

not legal in SA.
must be a sealed battery