When building a home backup power system for South African load shedding, the battery choice is arguably more important than the inverter. Your batteries determine how long you'll last in the dark, how many years before you replace them, and ultimately whether your investment makes financial sense.
The two technologies dominating the South African market are sealed lead-acid (AGM/Gel) and lithium iron phosphate (LiFePO4). Both work. But they are not equal — and the right choice depends on your budget, your usage pattern, and your long-term plans.
Before comparing costs, you need to understand depth of discharge (DoD) — because it changes everything.
Lead-acid batteries should not be discharged below 50%. If you have a 200Ah AGM battery bank, you only have 100Ah of safely usable capacity. Discharging deeper, consistently, accelerates degradation and kills the battery within months.
Lithium LiFePO4 batteries can be discharged to 80–90%. That same 200Ah lithium battery gives you 160–180Ah of safely usable capacity. You're getting nearly double the real-world energy from the same rated capacity.
This single fact reshapes the entire cost comparison.
+ Lower upfront cost
+ Widely available, any supplier
+ Compatible with virtually all inverters
+ No special BMS required
- Only 50% usable capacity
- 500–1,000 cycles lifespan
- Heavy and bulky
- Sensitive to heat (common in SA)
- Emits hydrogen gas during charging
- 2–4 year lifespan in daily use
+ 80–90% usable capacity
+ 3,000–6,000 cycles lifespan
+ Lighter, more compact
+ Faster charging
+ Better heat tolerance
+ Safe for indoor install (no gas)
+ 8–15 year lifespan
- Higher upfront cost
- Inverter must support lithium charging
- Fewer budget suppliers
Let's run the numbers using a typical South African home scenario: a 200Ah battery bank, discharged once daily during load shedding.
| Metric | 200Ah AGM Lead-Acid | 200Ah LiFePO4 Lithium |
|---|---|---|
| Approximate cost (2026) | R5,000 – R7,000 | R10,000 – R16,000 |
| Usable capacity (DoD) | ~100Ah (50%) | ~170Ah (85%) |
| Cycle life at rated DoD | ~700 cycles | ~4,000 cycles |
| Estimated daily use lifespan | 2 – 3 years | 10 – 12 years |
| Replacements over 10 years | 3 – 4 x | 0 – 1 x |
| Total 10-year battery cost | R15,000 – R28,000 | R10,000 – R18,000 |
South Africa's climate is not kind to lead-acid batteries. High ambient temperatures — particularly in Gauteng, the Northern Cape, and Limpopo during summer — dramatically shorten lead-acid battery life. For every 8°C above 25°C, lead-acid lifespan approximately halves.
Lithium LiFePO4 is significantly more tolerant of heat. While you should still avoid placing batteries in direct sun or near heat sources, they perform far more reliably in the temperature ranges typical of South African garages and utility rooms.
A 100Ah AGM battery weighs roughly 26–30kg. A 100Ah LiFePO4 lithium battery weighs 11–13kg. For a 200Ah bank, that's the difference between 52–60kg and 22–26kg. If your battery bank is in an awkward location — top shelf, upstairs, in a built-in cabinet — lithium makes installation and future servicing far easier.
Lead-acid still makes sense in specific situations:
| Brand | Origin | Notes |
|---|---|---|
| Pylontech | China | Most widely installed, excellent support, modular |
| Hubble Lithium | SA Brand (Chinese cells) | Local warranty support, popular with installers |
| FreedomWon | South Africa | Premium locally manufactured, excellent BMS |
| Revov | South Africa | Remanufactured EV cells, more affordable, good reputation |
| BSL Battery | China | Budget option, check warranty terms carefully |
If you're building a new backup power system for a South African home in 2026, lithium is the right choice in the vast majority of cases. The upfront premium pays for itself within 3–4 years through avoided replacements, and you get more usable power, better heat performance, and a lighter installation throughout.
If budget is the binding constraint, start with quality AGM lead-acid and plan your upgrade to lithium at the next replacement cycle. Use our power calculator to size your system correctly, or contact us for a customised quote on either technology.
Also see our guide: How to Choose the Right Inverter for Load Shedding in South Africa
In most cases, yes. Lithium batteries last 2–3 times longer than lead-acid, deliver more usable capacity per cycle, and perform better in South Africa's heat. Over a 10-year period the cost per kWh delivered is typically lower for lithium, making it the better long-term value despite higher upfront cost.
Often yes, but your inverter must be compatible with lithium charging profiles (usually a lithium or LiFePO4 setting). Check your inverter manual or contact the manufacturer. Most modern hybrid and UPS inverters support lithium batteries, but older models may not charge them correctly.
Quality LiFePO4 lithium batteries are rated for 3,000–6,000 cycles at 80% depth of discharge. Quality AGM lead-acid batteries typically deliver 500–1,000 cycles at 50% depth of discharge. This means a lithium battery can last 5–10 years in daily load shedding use, versus 2–4 years for lead-acid.
LiFePO4 lithium batteries are significantly safer than other lithium types. They do not produce hydrogen gas (unlike lead-acid) and are far more thermally stable. Most LiFePO4 home batteries are rated for indoor installation in a cool, well-ventilated space. Always follow the manufacturer's installation guidelines.
Common brands available in South Africa include Pylontech, Hubble Lithium, FreedomWon, BSL, and Revov (remanufactured EV cells). Pylontech and Hubble are among the most widely installed. Always buy from a reputable local dealer to ensure warranty support.