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australia:12vbatteries

12V batteries, battery boxes and power stations

see also:

  • I don't sell any of these nor do I receive any remuneration if you buy them, and I have not personally reviewed all of them, they are listed here to give you perspective

Introduction

  • an auxiliary deep cycle 12V battery of around 100Ah (1200Wh) is a great addition for your camping trip
  • in 2021, your best option is probably a LiFePO4 battery (see below for advantages over a traditional lead acid battery)
  • even without an offgrid charging system (solar or DC-DC from your car alternator), a reasonable size battery of 100AH will power most of your devices and even a car fridge for a few days with care, and without need for recharge.
  • for those on longer trips, an off-grid power re-charge will be needed
  • most 12V batteries come in a sealed maintenance free box with two terminals
  • many 12V batteries can be connected in parallel with similar capacity and chemistry batteries to create larger capacity
  • some 12V batteries can be connected in series to create 24V or 48V systems
  • while you could connect alligator clamps or M8 terminals to these and then to a cable with 50A Anderson plugs and an inline fuse to run your devices (there are lots of converter cables for Anderson plugs such as cigarette lighter, etc), a better option is for either:
    • install in a battery box
      • these provides added protection to the battery while minimising risks of short circuits of the terminals
      • they generally have a variety of output ports such as Anderson plugs (these can be used for charging the battery too), 10A cigarette lighter female sockets, USB out ports
      • they usually also have a voltmeter to help you roughly estimate how much capacity is left in the battery (a more accurate method requires installing a special capacity meter with a shunt wired to the battery)
      • lastly they have a On/Off switch to disconnect the battery from the ports
      • you will need to also buy a 240V AC-DC charger (preferably a 15A or 25A lithium charger - see below)
    • purchase an all in one “Power Station”
      • this has a fixed battery, ports, charger and often an AC inverter in the one fixture for convenience
      • the downsides are:
        • unable to replace the battery
        • generally have lower capacity eg. 50Ah
        • generally slow re-charge times (often only 5A)

Physical size considerations

  • battery size in volume terms is generally in proportion to the Ah capacity
  • rear seat floor of a car:
    • 48cm wide x 20cm deep (but could be deeper if move front seat forwards) - measure your own car
    • requires slimline models or a smaller capacity battery eg. 50Ah
  • height of hide in a Subaru Outback boot = 41cm
  • wall mounting on RV's or 4WDs:
    • consider slimline models
  • battery boxes are generally designed for sizes consistent with 80-120Ah batteries
    • larger batteries will not fit
    • smaller batteries may require additional spacers to avoid movement of battery within the box
  • interiors of vehicles get HOT on sunny days - this may severely impact the life span of the battery if exposed to long periods over 40degC
    • LiFePO4 batteries last much longer if kept below 30degC
    • even an August winter day in Melbourne will give around 30degC in the boot of a Subaru under the hide

Battery specifications

  • capacity is rated in Ah (amp hours)
    • this is easily converted to Wh (watt-hours) by mutiplying by voltage (ie 12)
    • 100Ah will run a 120W device for 10hrs (although you should only go down to 20% charge at most - so 8hrs is better)
      • a car fridge used carefully may only need 1A per hour
      • a “48W rated” car heated cushion will generally average 1A per hour as it cycles on and off
      • a 150W 12V car demister heating fan for your tent will use around 12.5A per hour and rapidly deplete your battery!
      • most laptops run at 65W
  • nominal voltage
    • this is the specified operating voltage for use as a single battery and for LiFePO4 batteries is usually 12.8V as they contain 4 LiFePO4 3.2V battery cells connected in series (some may have additional ones connected in parallel else well to increase capacity)
  • voltage range
    • LiFePO4 batteries have a Battery Management System (BMS) which will usually prevent:
      • over-charge - will cut off charging if voltage exceeds a specified amount (usually around 14.6-14.8V)
      • over-discharge - will cut off discharging if voltage falls below a specified amount (usually 10-11.7V)
  • life span is usually rated in number of cycles for a given depth of discharge (DoD):
    • the greater the amount to deplete the battery to each time, the less of these cycles you get
    • good LiFePO4 batteries are generally rated at least 2000-4000 cycles for 80% DoD at 25℃ and at discharge/charge rates of 0.2C
  • maximum charge / discharge rates
    • in general you will want to charge the battery at an optimum rate (this may be 0.2C but as long as it is above the manufacturer's minimum charge rate) without over-heating the battery as heat kills life span
    • charge/discharge rates are usually in amps but can be in terms of C where 1C is a complete charge or discharge of capacity within 1 hour (2C is within 30 minutes)
    • power stations often have limited charge rates of 5A
    • most batteries have a 0.5C charge (ie 50A max for a 100Ah battery) and thus charge in 2 hours
    • most quality batteries have a 1C continuous discharge (ie 100A max for a 100Ah battery) and thus discharge in 1 hour
  • ability to connect similar units in parallel
    • this allows increased capacity but needs care in ensuring similar capacity and chemistry batteries and similar charge cable lengths to each to provide efficient balancing
  • ability to connect similar units in series to increase voltage to 24V or 48V
  • weathersealing
    • usually rated in IP standards; you do not want lithium cells getting wet!
  • terminals
    • M6 or M8 bolt “button” terminals
      • these have a nut to hold down your cable's connector ring with M8 being more heavy duty than M6
      • the bolts are often removable for ease of storage etc
      • one should not exceed the maximum torque when tightening these nuts, although experienced users will tighten by feel
    • automotive post (AP)
      • these are the standard type of terminals in most car starter batteries and require a clamp type connector
  • smart electronics such as:
    • automatic self-heating when temperature falls below 5degC
    • SOC monitor capability
    • intelligent auto-balancing when connecting to same batteries
    • Bluetooth for smartphone app access to BMS and SOC

240V AC-DC chargers for 12V LiFePO4 batteries

  • NB. these are NOT needed for power stations as these generally have a built in charger
  • assuming you have a 100Ah LiFePO4 battery and you wish to charge it at the camp ground's laundry or other AC outlet and you don't want to be hanging around for many hours waiting for it to charge, then you should consider buying a high current (eg 25A) lithium charger albeit at higher cost, size and weight than low current chargers
  • you do need to check the max. rated charge rate for the battery to avoid overheating and damaging it but nearly all 100Ah LiFePO4 batteries should easily take a 25-30A charge rate.
  • you can potentially use two chargers in parallel for faster charge rates 1) however this may cause problems particularly as the battery is getting to full and needs cell balancing. Chargers generally turn output off momentarily to check voltage of the battery and if there is another charger going then it may not get an accurate reading, thus having multiple chargers running is probably not recommended, especially if each charger is not isolated to back current from the other charger by use of a schotkey diode to ensure current only runs one way. Do this at your own risk and with care!
  • these chargers will also charge lead acid, AGM, and lead calcium batteries
  • do not charge LiFePO4 batteries below 0degC or above 50degC.
  • Victron BlueSmart series have a smartphone Bluetooth app which allows you to change settings and monitor charging as well as retain a history of charging sessions. Plus the app lets you set them as DC out power supplies.

40A chargers

20-30A chargers

  • Victron BlueSmart IP22 12V 30A chargers
    • silent night mode which runs at half or quarter charge rate depending upon model
    • conventional screw-down electrical connections and is not shipped with cabling
    • 94% efficiency;
    • $AU344 for triple outlet charger can charge up to 3 batteries at once to max. total current of 30A
    • $AU329 for single output charger
  • Victron BlueSmart IP65 12V 25A
  • Renogy 20A charger

15A chargers

Battery boxes and Power Stations

Battery boxes

general characterististics

  • these not only house your battery but provide a range of very useful and convenient functions which may include:
    • ability to re-charge the battery via Anderson port or external terminals to allow either:
      • 240V input
      • solar panel input
      • DC input including from your car's main battery and alternator system
    • various DC output interfaces such as:
      • cigarette socket outlet
      • USB port
      • USB-C port to charge the latest laptops
      • 50A Anderson bidirectional plugs - you should aim to have at least 2 of these
      • 175A Anderson outlet - probably don't need this as you can use a jump starter with these batteries, the only other potential use if for high output devices such as 3000W AC inverters but these will drain the battery very fast!
    • possibly a built-in AC sine wave inverter with 240V output
      • HOWEVER, as the lead acid batteries are not designed for rapid depletion, only low current draw appliances should be run - higher draw appliances may need a petrol power generator with an AC inverter
      • a good one will cost around $AU499-699

examples of battery boxes with AC inverters

  • ArkPak 730P $AU699 - 300W Pure Sine Wave Inverter; the only battery box on the market that has a built-in AC-DC and DC-DC charger; battery management system and a dual-battery alternative; 50 amp Anderson socket; 2x 12V sockets; 1x 5V USB 2.1amp socket; 7 Stage smart charge; compatible with LiFePO4 although some report buggy battery status issues; 4.6kg;
  • Engel Smart Battery Box Series 2
    • $AU549, 300W AC inverter; Output Power: 1 x 12V 10A Cigarette Socket | 1 x 12V 10A Engel Posi Fit Socket | 1 x 12V 50A Anderson | 1 x 240V AC 300W Modified Sine Wave Socket | 1 x 5V 2.1A USB | 12V 100A External Terminals
    • supports LiFePO4 up to 130Ah

examples of battery boxes without inverters:

  • Dune battery box
    • light, has 2 Anderson plugs plus 1xcig, 2x USB, terminals, meter
    • on special for $AU69
    • stainless steel compact box with voltmeter/capacity meter/Bluetooth, 2x Anderson, USB, Cig lighter
    • PLUS 100Ah LiFePO4 battery
    • 32.3 x 19 x 19.5 cm; 14.5kg; $AU850 ($AU790 without Bluetooth monitoring)
    • $AU179 3.2kg; supports Lithium; 1 x dual USB output; 2 x cigarette plug outputs; 4 x 50A Anderson plug inputs/outputs; 1 x 175A Anderson plug output for jump starter leads (opt) or an external AC inverter (opt);
    • max. size battery: 330mm (l) x 180mm (w) x 240mm (h) (equates to 120Ah LiFePO4 battery)
    • 41x32x24cm external;
    • charging only via Anderson plugs; optional 50A Voltage-Sensitive Relay (VSR) kit;
    • make sure you make an Anderson plug connection to your AC battery charger otherwise you will need to unscrew the screws holding the lid down.
    • available in Melbourne from Every Battery Kensington
  • Ardent Heavy Duty battery box:
    • 2x Anderson plugs; 2xUSB, cig plug; circuit breaker; volt meter; ext. terminals;
    • max. battery up to 120Ah: 230H x 185W x 360L mm shortest battery length: 260mm;
    • 1.6kg; ext: 280H x 265W x 440L mm (too long)
    • $AU59
  • KT Portable box $AU99
    • lighter at only 1kg, top handle, 2x USB, 2x cig lighter outputs; charging via rapid charge battery charger terminals; for batteries up to 120AH;

Power stations

  • these have a battery and box all in one sealed unit
  • at present most of these are older lithium ion technology rather than LiFePO4
  • convenient but generally poor value for money and limited DIY repair options (batteries are generally not user replaceable)
  • eg.
    • Sunovo SPS300 18Ah
      • 18Ah 266Wh lithium ion; 3.5kg; $AU399
      • 5-6hr charge on AC;
      • 21Ah 225Wh lithium ion; 3kg; $AU499
      • 7-8hr charge on AC;
    • Sunovo SPS500 35Ah
      • 35Ah 504Wh lithium ion; 3.5kg; L23.5 x W14 x H21cm; $AU599
      • outputs: USB2 5V2A; USB3 5V/3A; 45W PD; 2xDC 12V/10A; 1xcig; 300W pure sine wave AC inverter
      • inputs: solar (5hr charge with 100W panel); 5-6h charge with AC; 6-8hr charge with car DC;
      • 45Ah 505Wh lithium ion; 5.8kg; $AU1099
      • 7-8hr charge on AC;
    • Companion Rover lithium 40AH Power Station
      • $AU599
      • LiFePO4; 6.5kg; 512Wh; 270 x 154 x 242 mm;
      • max. concurrent output 10A
      • max. solar charge rate 5A
      • outputs: USB 3.: 2 x 5V/2A, 12V/1.5A; USB-C: 1 x 5-20V 3A max. 60W; 2x DC5525 12-16.8V 10A DC Plugs; 1 x 12-16.8V/10A cig; 1 x 12-16.8V/10A 2-pin Engel-type; 12-16.8V 10A Anderson;
      • inputs: 14V 5A DC; 16.8V 5A AC, Anderson, 18-20V 5A direct solar (MPPT controller included in station)
    • Dometic PLB40:
      • 40Ah LiFePO4 battery; max output 15A; 9.08kg; 197 x 257 197 mm; IP44 rated; 10Amp ACDC charger;
      • integrated DC-DC charger offers three convenient ways to charge via: the vehicle 12 V socket, solar panel or AC power.
      • DC cable extension with Cig plug & Anderson connector
      • $AU849
      • 50Ah 518Wh Li battery; 500W AC inverter - 2 outputs;
      • 1x 18W USB QC; 2x USB; 1x 45W PD USB-C; 1x 12V 10A cig lighter; 2x 5mm DC 12-16.8V outputs; inbuilt MPPT solar regulator;
      • 7-8hr charge time on AC; 6.6kg; $AU1000
    • Companion Rover lithium 70AH Power Station
      • similar to above 40AH version; NMC (LiNiMnCoO2) battery; $AU1099; 6.8kg; 800 Charging Cycles down to 80% SOC;
      • max. charge rates: 240V AC 77-84W 5A; cig lighter 126W 9A; Anderson plug solar 13-30V 12A (MPPT controller included in station);
    • Nomad 100AH Lithium Power Distribution Unit V5
    • EcoFlow River 600 Max Power Station
    • EcoFlow Delta 1800W Power Station
    • Hyundai 1000W / 2000W max LiFePO4 Lithium Power Station AC/DC
      • $AU2199; 14.8kg; 84Ah;
      • outputs: USB 3.: 4 x 5V/3A, 9V/2A; USB-C: 1 x 18W, 5/9/12V; 2 x 5.5mm DC Plugs; 1 x 12V/10A cig; 2x 240V AC; 1 x EC5 150A Max jump starter;
      • inputs: 5-24V 120W solar; 240V 120W AC;
      • 160Ah, 2048Wh LiFePO4; 1500W AC inverter;
      • USB out; Anderson plug; DC 12V 6A out; DC 12V 10A cig lighter out; WiFi smartphone app; Solar MPPT Control System;
      • 34.5kg; $AU2195
      • 1500Wh LiFePO4?, 1000W AC pure sine wave inverter - two outputs;
      • PD USB-C out; 4x USB; 1x 12V 9A DC out;
      • 5.5-6hr AC recharge (3-3.5hrs with 2 inputs); solar MPPT (Maximum Power Point Tracking) charge controller built-in;
      • 17kg; $AU1869
      • 2000Wh LiFePO4, 2000W AC pure sine wave inverter - two outputs;
      • 2x wireless charging pads; 60W USB-C out; 4x USB; 1x 12V 10A DC out; 2x 12V 3A DC out; 1x 12V 25A out;
      • 5.5-6hr AC recharge (3-3.5hrs with 2 inputs);
      • $AU2599

12V LiFePO4 deep cycle batteries

pros and cons of LiFePO4 batteries

  • these are lighter, safer, but currently are much more expensive compared to a deep cycle lead acid battery
  • a 54AH LiFePO4 battery equates to 110AH lead acid as it can go down to full discharge instead of only about 50% discharge.
  • 5-10x the life of an equivalent Lead Acid AGM battery and weigh less than half as much and has far less self-discharge rates, retaining 80% of charge by 12 months compared with only 40% for typical lead acid batteries
  • charges 3-4x faster, some 100AH batteries charge in 1-2 hours!
  • More resistant to vibration, less likely to be damaged and have a more stable output voltage which tends to be maintained until capacity falls below 30%
  • LiFePO4 batteries are less likely to explode when over-charged and maintain charge longer than other lithium batteries and unlike other lithium batteries, do not suffer from thermal runaway
  • it should have a built-in battery management system to ensure all cells are charged evenly, and to provide short-circuit protection, reverse polarity protection and over-current protection as well as ensuring a consistent output
  • usually require a special lithium charger
  • Deep cycle ones are not suitable for use as a primary vehicle starting battery and cannot be used under the bonnet as it gets too hot
  • disconnect the loads when you are storing the battery for long periods and store at 30~50% SOC
  • avoid continuous maintenance or trickle charging
  • do not charge below 0C
  • there are many “cheap” LiFePO4 batteries on the market including some listed below - these may or may not have quality undamaged cells, quality build, or properly balanced cells and may have lower capacity than specified, shorter life spans and have specific requirements regarding charging, etc - do your research!
  • reputable manufacturers include:

models able to fit on floor of rear seats of cars

  • rear seat floor of a Subaru Outback is ~480mm wide by ~200mm deep (more if you move the front seat forward)
  • some of the Power Stations mentioned above will fit as well
  • remember to secure them so they don't become lethal missiles in an accident

compact, light 2.5-5kg 15-40Ah models

relatively small 6-8kg 50-55Ah models

    • 6.9kg; 18.8 x 16.4 x 14.8 cm (18cm total height including terminals); 8000 cycles
    • $AU390 on special ($AU450 with bluetooth)
    • designed to be wall mounted so not as good for the floor of a rear seat
    • can be connected in parallel or series up to 4 of same units
    • 7kg; 300x90x210mm; M6 stud; built in cig lighter port one end and 2x floor-level mounted Anderson ports at other end;
    • $A599 ($AU499 on special)
    • 7kg 648Wh; charge 25-55A; IP65 waterproofing; can cycle up to 5000 times at 50% depth of discharge; can use most existing chargers; can be connected in parallel/series; $AU499 based in Perth, WA
  • VoltaX 12V 50Ah
    • ~6.6kg 640Wh; charge 10-50A; requires own Li charger; $AU329
  • DryPower Deep Cycle Lithium 12.8V 50AH 640Wh battery
  • Drypower 12.8V 55Ah Lithium Iron Phosphate (LiFePO4)
    • 197x166x171h mm; 6.7kg; 2000cycle 80% DOD; M8 terminals;
    • $AU399;

100-130Ah slimline models

10-14kg 100-140Ah similar size to standard lead acid batteries

Lead acid batteries

characteristics

  • these may be a deep cycle or dual purpose battery
  • A deep-cycle battery is a battery designed to be regularly deeply discharged using most of its capacity, unlike a normal starter battery which is designed to only use a small part of its capacity in a short, high current burst to crank the engine.
  • deep cycle batteries cannot be used to crank start your vehicle, but a dual purpose one can.
  • there is a trade off between the battery's depth of discharge and the number of cycles of discharge and recharge it is capable of and there is an inverse relationship between these
  • these deep cycle batteries are generally designed to discharge slowly over 20-100hrs such as with a fridge, and if they are discharged rapidly such as over 1 hour, you will only get to use around half of the usual capacity and the number of cycles will be reduced
  • none of these lead acid batteries should be fully discharged as this will shorten their life span, and should only be discharged to 20% of capacity
  • Absorbent glass mat (AGM) batteries handle higher temperatures better, self-discharge more slowly, will charge more quickly (usually within 3hrs from a standard car alternator), have deeper discharge depths, are totally sealed, more robust, do not need topping up with water, can be safely mounted inside a car as they do not need to be vented externally
  • these can explode if over-charged or their release valve fails (if they have one)
  • these will usually set you back around $AU230
australia/12vbatteries.txt · Last modified: 2022/04/15 09:37 by gary1