LiFePO4 Battery Sizing for Pakistani Homes 2026 — 5/10/15 kWh Solar Storage BoM
What size LiFePO4 battery does a Pakistani home need?
Match battery kWh to the energy you need to ride through load-shedding + night-time hours. 5 kWh covers a typical 1-ton AC + 4 LED lights + ceiling fans + WiFi for ~4 hours. 10 kWh covers a 1.5-ton AC + small fridge + lights + fans + appliances for ~6-8 hours overnight. 15 kWh covers a full 5 kW house through a 12-hour load-shedding + grid outage window. Pakistani sweet spot: 10 kWh at 51.2V (16S LiFePO4 cells) paired with a 5-7 kW hybrid inverter and 5-7 kWp solar array. Full installed cost: PKR 700K-1.2M.
Battery sizing math
Step 1 — list backed-up loads:
- 1 × 1.5-ton AC: 1,500 W (inverter type) running, 700 W average
- 1 × fridge: 150 W average (cycling)
- 8 × LED lights: 80 W total
- 4 × ceiling fans: 280 W
- 1 × TV + WiFi: 80 W
- Total continuous: ~1,290 W average; ~2,000 W peak (AC compressor kick-in)
Step 2 — multiply by autonomy hours: 1,290 W × 6 hours = 7,740 Wh = 7.7 kWh. Add 20% safety/DOD reserve → ~9.3 kWh battery. Round up to 10 kWh nominal.
Step 3 — pick voltage: 51.2V (16S LiFePO4, 51.2V × 200Ah = 10.24 kWh) is the most common Pakistani standard. 48V nominal is older 4×12V lead-acid sizing; LiFePO4 typically labelled 48V but actually 51.2V nominal.
BoM — 10 kWh LiFePO4 Pakistani home install
| Component | Spec | PKR |
|---|---|---|
| LiFePO4 battery | 51.2V 200Ah rack-mount (~10.24 kWh) with BMS | 400,000-700,000 |
| Hybrid inverter (5 kW) | Solar + battery + grid + generator inputs | 200,000-350,000 |
| DC breaker (battery-inverter) | 2P 250A 80V DC for battery loop | 12,000 |
| DC fuse (battery-side) | DC fuse 300A NH00 80V (between battery + inverter) | 3,500 |
| Battery cabling | 50 mm² 2-core flexible copper, 2 m | 6,500 |
| DC SPD (PV side) | YCS6-C 2P 1000V Type 2 | 3,500 |
| PV string protection | DC breaker 2P 32A 1000V + 2× DC fuse 15A PV | 6,000 |
| AC DB on inverter output | 2P 32A MCB + 30 mA RCBO + AC SPD | 6,500 |
| Battery enclosure / rack | Wall-mount or floor cabinet | 10,000-25,000 |
| Ventilation + cooling fan | DC fan + duct for battery room | 3,500 |
| Installation labour | 2-day install team | 25,000-40,000 |
| Total (battery system only, no solar) | ~PKR 700,000-1,200,000 |
LiFePO4 vs other Pakistani battery options
| Chemistry | Cycles to 80% | DOD | Cost / kWh installed |
|---|---|---|---|
| Lead-acid (flooded) | 500-800 | 50% | PKR 30,000-50,000 |
| Tubular gel/AGM | 1,500-2,500 | 50% | PKR 45,000-65,000 |
| LiFePO4 | 3,000-8,000 | 80-90% | PKR 50,000-100,000 |
| NMC Lithium | 2,000-4,000 | 80% | PKR 60,000-120,000 |
Why LiFePO4 wins for Pakistan: longest cycle life (8 + years on daily cycling), deepest DOD (use 80-90% instead of lead-acid's 50%), tolerates Pakistani 45°C summers without thermal runaway risk that NMC has. Higher upfront cost amortises to lowest cost-per-cycle.
Common Pakistani battery-install mistakes
- No DC fuse between battery and inverter — battery short circuit pumps 10,000+ A into the cable until it melts. DC fuse blows in milliseconds, cable saved.
- 50% DOD assumed on LiFePO4 — you bought 80% capacity headroom; use it. Set hybrid inverter to 20% min SOC, not 50%.
- No battery ventilation — LiFePO4 doesn't off-gas but the BMS electronics dissipate heat. Pakistani summer 45°C ambient + 30°C extra inside box = thermal derating + BMS faults. Add a small DC fan + grille.
- BMS communication not wired — without RS485 / CAN comm between battery and inverter, the inverter doesn't know real SOC, can over-discharge or skip the float stage. Always wire the BMS-inverter comm cable.
- Parallel-connecting two different battery packs — one new + one old, or different chemistry. Charge / discharge unbalanced; eventually fails. Match age + chemistry + brand.
- Battery too far from inverter — 50 mm² × 5 m run = 0.5 V drop at 200 A. Reduces system efficiency by 1-2%. Keep within 2 m.
Buy + related
LiFePO4 buyer guide · DC breakers · DC SPDs · Inverter selection guide