LiFePO4 vs AGM for overlanding — cost per cycle comparison done properly
This comes up constantly so let me give you the detailed breakdown based on real-world experience in Johannesburg.
The technology: The cost argument for LiFePO4 is now clear. A quality 100Ah LiFePO4 at R5,500 gives you 6,000 cycles at 90% depth of discharge. The equivalent AGM at R2,200 gives you 400 cycles at 50% DOD. Work out the cost per kWh over the lifespan — LiFePO4 wins by a factor of 4–6x. Freedom Won and Hubble Lithium are the SA brands with the best track record. BSL is newer but getting good reviews.
Pricing in SA (2025): R4,500–R7,000 per 100Ah depending on brand and supplier. Get at least 3 quotes — pricing varies significantly between installers and online suppliers.
My setup: 177Ah LiFePO4 battery, 328W solar panel, Victron SmartSolar MPPT 100/20 controller, and a Redarc BCDC1225D for DC-DC charging from the alternator. Total investment: R28,000 all-in. It powers a Dometic CFX3 45 fridge 24/7 and runs LED lights, phone charging, and a 12V air compressor without any issues.
Common mistakes to avoid: Cheap MPPT controllers that misreport battery state — false readings lead to undercharging or overcharging.
Happy to share my wiring diagram or go into more detail on any component. This stuff seems complicated but it really is not once you understand the basics.
3 Replies
What MPPT controller are you using? I am running a Victron SmartSolar 100/30 and it has been faultless. The Bluetooth monitoring via the VictronConnect app means I can see exactly what the panels are producing and what the batteries are doing in real time. No more guessing.
This comes up constantly so let me give you the detailed breakdown based on real-world experience in Johannesburg.
The technology: The cost argument for LiFePO4 is now clear. A quality 100Ah LiFePO4 at R5,500 gives you 6,000 cycles at 90% depth of discharge. The equivalent AGM at R2,200 gives you 400 cycles at 50% DOD. Work out the cost per kWh over the lifespan — LiFePO4 wins by a factor of 4–6x. Freedom Won and Hubble Lithium are the SA brands with the best track record. BSL is newer but getting good reviews.
Pricing in SA (2025): R4,500–R7,000 per 100Ah depending on brand and supplier. Get at least 3 quotes — pricing varies significantly between installers and online suppliers.
My setup: 177Ah LiFePO4 battery, 328W solar panel, Victron SmartSolar MPPT 100/20 controller, and a Redarc BCDC1225D for DC-DC charging from the alternator. Total investment: R28,000 all-in. It powers a Dometic CFX3 45 fridge 24/7 and runs LED lights, phone charging, and a 12V air compressor without any issues.
Common mistakes to avoid: Cheap MPPT controllers that misreport battery state — false readings lead to undercharging or overcharging.
Happy to share my wiring diagram or go into more detail on any component. This stuff seems complicated but it really is not once you understand the basics.
— werner_dp
On the alternator damage question — it is a real risk with large lithium banks if you do not manage the charge rate. A DC-DC charger (Redarc BCDC or Victron Orion) limits the current drawn from the alternator to a safe level. This is not optional if you have more than 100Ah of lithium connected to your starting circuit.
The Eskom situation is interesting. My view: the 224 loadshedding-free days is excellent progress but I am not dismantling my solar system. Load reduction on overloaded feeders will continue regardless of Eskom's generation performance. And a home battery system has value beyond loadshedding — cheaper overnight electricity from time-of-use tariffs, backup during faults, and off-grid capability when you need it.