In dual battery setup, a DC DC charger allows you to charge an auxiliary battery from the alternator whilst driving. With the DC DC charger, the main battery remains unaffected and always ready to start the car. And the DC DC charger can activate lower input voltage operation to suit vehicles with smart alternators.This 12V DC DC battery charger can utilize a solar panel or a starting battery linked to the alternator, while giving the priority to a solar input to place less load on the alternator. The DC to DC charger is suitable for LiFePO4 and lead acid: AGM, gel & calcium batteries, and allows you to re-select the battery during charging. With the memory function of this battery to battery charger, you dont need to re-select the same battery type every time. And 6-stage charging is engineered for better maintenance & longer lifespan of battery. If youre planning an off-grid camping, this 40A DC DC battery charger will be your perfect companion for a dual battery setup.
In dual battery setup, a DC DC charger allows you to charge an auxiliary battery from the alternator whilst driving. With the DC DC charger, the main battery remains unaffected and always ready to start the car. And the DC DC charger can activate lower input voltage operation to suit vehicles with smart alternators.This 12V DC DC battery charger can utilize a solar panel or a starting battery linked to the alternator, while giving the priority to a solar input to place less load on the alternator. The DC to DC charger is suitable for LiFePO4 and lead acid: AGM, gel & calcium batteries, and allows you to re-select the battery during charging. With the memory function of this battery to battery charger, you dont need to re-select the same battery type every time. And 6-stage charging is engineered for better maintenance & longer lifespan of battery. If youre planning an off-grid camping, this 40A DC DC battery charger will be your perfect companion for a dual battery setup.
in 2 offers
The lowest price for 12V 40A DC to DC Battery Charger With MPPT Solar Battery Dual right now is $185.00 at Harvey Norman, compared across 2 retailers.
The all-time low was $185.00 on 7 Nov 2025. That's the lowest price we've ever tracked — a great time to buy.
Prices last updated 9 June 2026.
12V 40A DC to DC Battery Charger With MPPT Solar Battery Dual
In dual battery setup, a DC DC charger allows you to charge an auxiliary battery from the alternator whilst driving. With the DC DC charger, the main battery remains unaffected and always ready to start the car. And the DC DC charger can activate lower input voltage operation to suit vehicles with smart alternators.This 12V DC DC battery charger can utilize a solar panel or a starting battery linked to the alternator, while giving the priority to a solar input to place less load on the alternator. The DC to DC charger is suitable for LiFePO4 and lead acid: AGM, gel & calcium batteries, and allows you to re-select the battery during charging. With the memory function of this battery to battery charger, you dont need to re-select the same battery type every time. And 6-stage charging is engineered for better maintenance & longer lifespan of battery. If youre planning an off-grid camping, this 40A DC DC battery charger will be your perfect companion for a dual battery setup.
In dual battery setup, a DC DC charger allows you to charge an auxiliary battery from the alternator whilst driving. With the DC DC charger, the main battery remains unaffected and always ready to start the car. And the DC DC charger can activate lower input voltage operation to suit vehicles with smart alternators.This 12V DC DC battery charger can utilize a solar panel or a starting battery linked to the alternator, while giving the priority to a solar input to place less load on the alternator. The DC to DC charger is suitable for LiFePO4 and lead acid: AGM, gel & calcium batteries, and allows you to re-select the battery during charging. With the memory function of this battery to battery charger, you dont need to re-select the same battery type every time. And 6-stage charging is engineered for better maintenance & longer lifespan of battery. If youre planning an off-grid camping, this 40A DC DC battery charger will be your perfect companion for a dual battery setup.
Last updated at 09/06/2026 08:36:54
Atem Power DC to DC Battery Charger 12V 40A
Mobi 12V 40A DC to DC Battery Charger MPPT Dual Battery AGM Lithium LifePO4
Free delivery between 15–19 June
originally posted on sunyee.com.au
Easy to install and works very well with my 209ah agm battery and 2 x 250w solar panels. Clear light display indicates how the charger is working.
originally posted on ebay.com
The build quality is very good and it has no worries keeping my aux battery charged up. Having the solar function as well makes it so easy to fit my solar panel when needed.
originally posted on ebay.com
Charges battery quickly does isolate main battery from auxiliary battery but unit draws 1.2amps while in standby mode from the main battery so it flattens main battery anyway , I have 2 units and both do the same had to install a relay triggered by the ignition to isolate dcdc charger so defeats the purpose of having as an isolation device.
| Suitable Battery Type | AGM/Gel/Lead Acid/Calcium/LiFePO4 |
| Battery Range | 120-1200Ah |
| Input | DC Battery:13-16 Volts Solar Input:16-25 Volts |
| Max Output Current | 40A |
| Minimum Start Voltage | 2.0 Volts-For battery being charged |
Atem Power DC to DC Battery Charger 12V 40A
Mobi 12V 40A DC to DC Battery Charger MPPT Dual Battery AGM Lithium LifePO4
Free delivery between 15–19 June
Easy to install and works very well with my 209ah agm battery and 2 x 250w solar panels. Clear light display indicates how the charger is working.
The build quality is very good and it has no worries keeping my aux battery charged up. Having the solar function as well makes it so easy to fit my solar panel when needed.
Charges battery quickly does isolate main battery from auxiliary battery but unit draws 1.2amps while in standby mode from the main battery so it flattens main battery anyway , I have 2 units and both do the same had to install a relay triggered by the ignition to isolate dcdc charger so defeats the purpose of having as an isolation device.
Stopped working six weeks into my trip to North QLD.
Haven’t installed yet but expect great things
I bought 2 of these DC-DC charger over the past year. They are easy to wire and solid build
I purchased this unit because my vehicle has a smart alternator. I have installed it and unit looks to be working as lights are on, not sure why they remain illuminated for a few hours after switching ignition off. I have not yet done a trip to see if it is functioning correctly
Haven't installed yet will give a better review after install an running for a while
This dc charger only outputs at 13.2 volts so it WILL NOT fully charge a Lithium battery EVER
Great little unit, happy with performance so far. Would be nice if built in, to know amps being pumped in otherwise guessing via external ramping voltage readout
| Suitable Battery Type | AGM/Gel/Lead Acid/Calcium/LiFePO4 |
| Battery Range | 120-1200Ah |
| Input | DC Battery:13-16 Volts Solar Input:16-25 Volts |
| Max Output Current | 40A |
| Minimum Start Voltage | 2.0 Volts-For battery being charged |
