Dual Battery Systems

Running a fridge or camping lights and even charging the camera via an inverter, all put a strain on your original battery. A dual battery management system is the answer. Here at TJM we offer a range of dual battery management and charging systems available for all types of requirements. If you want a cold drink and still be able to start the car in the morning then read on because this is for you.

Notes to consider when choosing Dual battery management systems,

Temperature compensating Alternators

Some post 2000 model vehicles have temperature compensating alternators. Mainly vehicles fitted with common rail diesel engines utilise this style of alternator. The temperature compensationg alternator will charge at approx 14V when the engine is cold, and decreases to 13.4V when the engine reaches operating temperature. For this reason, the alternator may only charge a dual or multi auxiliary battery system to 60-70% state of charge at best, depending on the battery chemistry type used.

Known vehicles with this style of alternator - Toyota Hilux, Prado, LC200 LC7679 D4D Common Rail Diesel. Petrol Kluger 2010 on and BF Falcon

Variable Voltage Alternators

Some vehicles released in late 2010 onwards with common rail diesel and petrol engines have variable voltage alternators that are on the vehicle CANBUS. These alternators vary output based on driving conditions at the time. The range of voltage can be between 12.3V and 15V For this reason, the alternator may not charge a dual or multi auxilary battery bank at all times, and may apply too high a voltage for the auxliary battery chemistry type at other times. 

Known vehicles with this style of alternator - Nissan Navara D40, R51 Pathfinder 2011 onwards V6 Diesel only. Hyundai Santa Fe 2010 +, Range Rover 4 2011 +, Ford Ranger 2011 +, Pajero 2012 +, Mazda BT-50 2011, Land Rover Disco 4, Isuzu D-Max 2012 + & Holden Colorado 2012 +

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Dual battery charging systems, extra batteries, management systems and battery monitors.  Whether you’re planning to travel the outback or just want to keep the food cold in the 12 V fridge on a shopping trip, TJM have you equipped when it comes to battery backup charging. With the top of the range IBS System or DBS system, you’ll have the extra power to run a fridge, electric winch auxiliary lighting or even charging the camera battery. For the no fuss battery management system TJM Red Centa and Megatronics battery system will also keep everything charged.

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Battery management, Battery isolators, DC to DC chargers whatever your battery usage is outside of starting the car Redarc and TJM can have you equipped with state of the art charging systems, Take the new 150 Prado with its regulated alternator, without the use of the DC to DC charging system you are not achieving the full charging results that would required to keep the auxiliary battery at its full charge.

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Baintech Power top                                                              



Projecta Power Hub 

Download power hub release front page.pdf

This dual battery system is something out of the box. For all those vehicles that do not have the facility to mount a dual battery under the bonnet or don't want a system mounted permanently! Welcome to the Power Hub & Baintech Power Top. In stock now only at TJM Brendale. 


Lead Crystal Batteries - Make a change for the better watch this small video for more information. With 3 Year warranty and a depth of dis-charge second to none this is the battery for your camping needs


Supercharge batteries - More power, Longer life TJM Brendale have persoanlly tested and used these batteries and are confident the Deep cycle range and All Rounder range of batteries linked to one out quality Battery management systems is the ticket to holding charge for longer.

All Rounder - Starting and deep cycle battery all in one. Full 12 month warranty, High denstiy plate formulation for superior cranking with cyclic ability. Improved heat and vibration tolerance for longer service life. Maintenance-free "no need to add water"



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* Please note suppliers may advertise prices that do not include freight and fitting.