australia:12v_evcars
Table of Contents
12V batteries, EV cars and camping
see also:
Introduction
- most fully EV cars have high voltage lithium ion battery systems with capacities of around 75kWh and give around 500km combined highway/city driving range (assuming no load or towing)
- ie. you will use about 150Wh to drive 1km
- charging these on home 240V AC generally requires a Type 2 AC charger and a special 32A circuit to be installed which can then charge at around 7kW for single phase circuits or at 22kW for three-phase circuits
- charging these via Tesla's 150kW DC fast charging systems can get from 10-80% charge in 30 minutes
- actual charge times vary with temperature and battery state (most lithium batteries only like to be charged at 0-50degC)
- most cars generate electricity for re-charging batteries and other purposes
- a petrol or diesel engine does this via an alternator which has a rotor that spins within a magnetic field created by field coils, inducing voltage in the stator windings per Faraday's law
- when current demand rises (e.g., from headlights, air conditioner, running a winch, or DC-DC power to a 12V battery), the voltage regulator boosts field current to maintain output voltage. This strengthens the magnetic field, increasing the magnetic drag (Lenz's law opposes the motion), so the rotor experiences higher opposing torque which in turn pulls more power from the engine, enriching the fuel-air mix or slowing RPM slightly, thus burning more fuel
- hybrid electric cars use a generator to produce electricity - often when the car is braking, but for PHEV's also from the petrol engine driving the generator to ensure the main batteries are kept charged above 20-30% (or at 80% in charge mode) - engine-driven generator is more efficient than alternator conversion for high voltage battery charging.
- running an air conditioner will drain the battery faster if there is no petrol engine
- an air conditioner generally uses 1-3kW of electrical power
- in a petrol car, this results in a 10-20% fuel consumption increase for city driving (a bit less for rural driving)
- in a full EV, this will drain your batteries by 1-3kWh for every hour in use (at 100kph you would use ~15kWh every hour without the air conditioner on, hence air conditioner reduces mileage by about 10%)
- Be very careful with river crossings in electric vehicles!
- whilst most have battery systems are waterproofed to IP67/68, this usually only rates them to being submerged for under 30 minutes - more prolonged submerging generally requires safety checking and may require batteries to be replaced to avoid subsequent fire risk
- most vehicles are rated for water levels up to sills only and then only for short periods
- older batteries may have developed compromise to the water proofing and this could create an electrocution risk to occupants although this risk seems low
- furthermore, big rocks or holes risk physical damage to the underbody/battery case rather than just water exposure
- as with a non-EV 4WD, “if in doubt, don’t cross,” but if you decide to cross, check the current and path, stay at or below the manufacturer’s wading depth, go in slowly to form a bow wave, and avoid stopping midstream
Pros and cons of PHEV's for camping
- a PHEV plugin hybrid electric vehicle has both batteries (which need plug in charging) and a petrol engine - but this adds complexity to mechanics and only has ~70km electric drive range
- PHEV's are generally best around city areas for short trips within the battery driving range and then they can be plugged in overnight to be recharged
- they are a safer option for camping than a fully electric EV given you can drive out of a remote area even if the battery is nearly flat, and driving will recharge it, and if there are no electric charging stations, you can just re-fuel with petrol
- by default, the battery is used primarily, and the petrol engine only activates if battery depletes, heavy acceleration demands extra power, or temperatures require it, and then hybrid mode is activated where both petrol and battery (if not flat) are used optimally and the battery is charged to maintain levels of 20-30% state-of-charge while driving
- most have a CHG mode which forces the petrol engine on to charge the battery via an integrated generator allows efficient on-demand battery recharging up to ~80% state-of-charge while driving but the cost is substantial loss of fuel efficiency dropping by some 35% - there is no belt-driven alternator
- for most camping trips, you would probably use petrol for most of the driving (although you cannot turn off the EV component) and you may get to use the batteries to provide some power at the camp site as well as for your car fridge
- unlike full EVs you will not be stranded at a remote camp site if the PHEV battery goes flat
- jump starting is only needed if the separate 12V auxiliary battery (usually located in the rear cargo area) is fully flat, which powers accessories and initial startup electronics (jump start terminals though are generally under the hood for easy access)
- NOT to be confused with a hybrid vehicle in which there is a small battery which gets charged when the vehicle is braking but mainly runs on petrol engine albeit at only 2-7.5L/100km (eg. a 2025 Subaru Forester hybrid is officially rated around 6.2 L/100km whereas the pure petrol model is rated at 7.9L/100km)
example PHEVs with reasonable ground clearance and AWD or 4WD
- Mitsubishi Outlander PHEV
- AWD, quoted ground clearance around 190 mm and at 4710 mm is 170mm shorter than a Subaru outback and thus has less boot space at 480L (vs 520L for the Outback)
- more power (225kW combined vs 183kW) and torque (450Nm vs 350Nm) compared to a turbo 4cyl Outback but slower to 100kph (7.9sec vs 6.8sec)
- the US Trail edition (not announced for Aust as yet) increases clearance to 220mm, adds all-terrain tires, skid plates, rugged styling like black cladding and roof rails, and enhanced Super All-Wheel Control modes for trails
- Trumpchi (GAC) GS7/GS8 PHEV family
- Chinese-market PHEV SUVs with AWD and reported 200 mm ground clearance
- Toyota RAV 4 AWD PHEV
- scheduled to hit Australian showrooms in Q3 2026
- 4.6m long, 1.68m high, ground clearance 190–200 mm
- has a 18.1 kWh battery which is a quarter that of a full EV and equates to a ~1400Ah 12V battery
- highway figures typically range from 6.4-8.6 L/100km in petrol mode
- 2.4L 4cyl engine alone gives 134–136 kW power and 227Nm torque 0-100 km/h time of about 6.0 seconds
- front electric motor gives 134kW and 270Nm torque, rear electric motor gives 40kW and 121Nm torque
- combined 227kW
- 1500kg braked towing capacity
- 672L cargo capacity with rear seats up but not as much usable capacity as Subaru Outback
- GR Sport version features 20“ wheels instead of 19”, GR-tuned suspension for firmer handling and reduced body roll, sport-calibrated steering for better feedback, and enhanced chassis rigidity but seem it has same ground clearance as standard XSE version which is probably better for gravel roads than the GR
- as of Feb 2026, there do not appear to be any PHEVs well suited to offroad with ground clerances > 210mm and AWD or 4WD power trains
Pros and cons of fully electric vehicles (EVs) suitable for camping
- electric vehicles have a lot more torque than petrol vehicles and this can be handy, especially if steep ascents or towing (but towing will reduce driving range as it does in non-EV vehicles)
- potentially have less to go wrong as they are more simple systems however a flat battery will create major issues (or worse a battery fire)
- they reduce (but not eliminate) the need to bring heavy bulky 12V batteries for your camping needs, but you will probably still want at least on 12V battery:
- you don't want to be running cables from your EV into your tent
- you don't want to be running a power hungry device for a long period from your EV in case you flatten it (a big risk with car fridges, portable heaters, etc) - better to accidentally flatten your 12V battery
- you may need power at camp when the EV is not there
- a flat EV battery will leave you stranded and this is not an easy situation to resolve!
- a solar panel is NOT going to be an adequate option to recharge your EV!
- most camping solar panels only provide 200W power in full sun, so this would require 20hrs in full sun to recharge a 300Ah 12V LiFePO4 battery which would then provide 25km drive time (see below) if you also have all the other gear that is needed for this style of charging, and it is compatible with your EV
- a petrol generator might be a better backup
- this would require a slow 240V AC charging capability and charger and you have to be allowed to run a generator
- if the local power grid goes down you will not be able to re-charge
- storms can cut power for extended periods in regional areas
- mind you, you may not be able to get fuel either so this may be a mute point although fuel is easier to be carted in
- EVs are practically silent - animals and people will NOT hear you coming - you need to be extra vigilant, especially in camp grounds and especially when kids are around!
- in 2026, Ford ditched plans for ongoing production of its much criticized fully EV F-150 Lightning - their US EV pickup which resulted in US$4.8 billion loss due to its EV division alone for the 2025 year, and instead is no prioritizing hybrids rather than full EV - Ford total loss for 2025 was US$8.2 billion and US$5.9 billion in 2024 and they expect short-term losses of US$19.5 billion.
- full EV probably is not going to make it with current technologies for those with 4WDs, especially if they tow
Example fully electric vehicles suitable for camping
Subaru Trailseeker
- coming mid 2026
- jointly designed with Toyota - wheelbase now similar to Toyota's gold standard as per Landcruiser
- 74.7kWh and give around 533km combined highway/city driving range
- Tesla's 150kW DC fast charging systems can get from 10-80% charge in 30 minutes
- 22kw 3 phase charging
- no need for a CVT transmission
- 2 electric motors which provide 280 kW power and a 0–100 km/h time of just 4.4 seconds
- 1500W AC V2L output port
- 1500kg braked towing capacity - although towing will dramatically drop driving range
- similar off-road capabilities as a Subaru Outback:
- 211mm ground clearance
- Symmetrical All-Wheel Drive (AWD), X-Mode traction control and Downhill Assist Control
- seems to be lots of fun in slippery conditions: https://www.youtube.com/watch?v=bDlvUUzaewM
- although Subaru has announced a full EV TrailSeeker for 2026, Trump's tariffs has resulted in plummeting US sales and 70% of their market is the US so this may severely impact their future which is now leaning more to utilising Toyota hybrid tech
Using your EV battery for camping
- many have an inbuilt 1500W AC inverter to provide an AC power port outlet but this will drain your battery if using high wattage devices for too long
- you can use the traditional 12V 10A cigarette lighter port to run a car fridge, etc
- charging your 12V LiFePO4 battery
- EVs do not have an alternator so you can't just connect a DC-DC charger to charge your 12V battery, but many have high voltage outlets which can be potentially be used for DC-DC charging of your 12V LiFePO4 camping battery (via a DC-DC charger)
- preferably you don't want to use the EV's AC V2L output for this as this loses efficiency in converting DC to AC then back to DC
- JUST make sure you don't flatten the EV's batteries or you will be stranded and need to be towed out - jump starting is not going to work!!!
- your friends are not going to be able to go to the nearest town and bring back some electricity - unless perhaps if they also had an EV with Vehicle-to-Load (V2L) AC output and your car allowed 1500W 240V AC charging!
Emergency charging an EV using a 12V LiFePO4 battery
- assuming you have a slow AC charger to connect an AC inverter (this may not apply to all EVs!):
- if the system allows it, you would need to use a large 300Ah battery (or multiple batteries in parallel) to allow total 150A /1700W discharge current (and this will need a 2000W AC inverter and 1AWG cables with 150A fuse)
- at 150A discharge current, this would fully drain your 300Ah 12V battery in 2hrs and provide ~4000Wh charge to your car which would enable you to drive it about 25km
- that's a lot of effort and cost for not much gain! - Best not to allow your EV battery go flat whilst camping!
- PS. a 100Ah battery alone will not allow the required 150A discharge current, you would need at least two in parallel to achieve this
australia/12v_evcars.txt · Last modified: 2026/03/03 10:27 by gary1