i Series Electric Motors –
The Complete UK Guide

A reconditioned BMW i Series electric motor typically costs £3,000–£5,000 supply only [BMW-QUOTE] - with dual-motor models costing more. Battery replacement costs £5,000–£15,000+ depending on model and battery size. Fitting adds £650–£1,500. Use our calculator for a personalised figure.

The i4 eDrive40 - proven Gen5 eDrive technology, single motor simplicity, and established battery technology. The iX xDrive40 is also excellent. Avoid the early i3 60 Ah (battery degradation) and the i8 (hybrid complexity).

No model outright - but an early i3 60 Ah (2013–2016) without a battery health check is the one purchase we consistently advise against. The i8 is a fantastic car but carries hybrid complexity - budget for specialist servicing. A 42 kWh i3, i4, or iX has no such caveat.

By issue: whining noise under load (motor bearing wear), reduced range (battery degradation), increased charging times (battery degradation), charging port failure (charging system), reduced power (i8 hybrid system). On the i3, any significant range reduction is a warning sign. Caught early, it's a service; ignored, it's a £3,000–£15,000+ replacement.

Depends entirely on model and component. Against a £20,000–£30,000 i4, a £3,000–£5,000 motor replacement is 10–25% - safe. A £7,000–£11,000 battery replacement is 23–55% - ⚠️ watch. Against a £8,000–£15,000 early i3, a £5,000–£10,000 battery replacement is 33–125% - walk away. Our 60% BMW threshold is the line: below 60% is safe; above it, run the maths carefully. Use our calculator for your car.

i4 eDrive40 with Gen5 eDrive - 286 hp, 340 miles of range, proven technology, and sensible used values (£20,000–£30,000). For the budget option, i3 120 Ah (42 kWh) - the largest battery is the one to buy; budget for a battery health check before purchase. For the future, Neue Klasse i3 - 469 hp, 800V architecture, and near-M3 power. For the collector, i8 - a future classic with hybrid complexity.

Listed on the VIN plate and in the vehicle documentation; the battery capacity is also visible in the iDrive system under charging settings. Or tell us your model year and variant (i3 60 Ah, i4 eDrive40, iX xDrive50) and we'll identify it - 20+ vetted specialists will confirm it for free.

The i4 is significantly more premium and better built than the Model 3 - the i4's interior quality and build quality are superior. The Model 3 has better charging infrastructure access (Tesla Supercharger network) but the i4 is closing the gap. The i4's Gen5 eDrive is proven and reliable. Buy the i4 for premium quality; buy the Model 3 for charging network access. Read the full head-to-head →