| O2a | O2b | ||
| 16 cell | 8 cell | ||
| Description | Device | Cost | Cost |
| μC | simple microchip | £0.70 | £0.70 |
| Opto isolator control | EL3H7-G | £0.13 | £0.13 |
| Full bridge PWM | LM5045 | £1.78 | £1.78 |
| MOSFET | NVMFD5C446NL | £1.21 | |
| NVMFS6H801N | £2.68 | ||
| i2c isolation | ISO1542 | £1.73 | £1.73 |
| Components total | £7.03 | £5.56 | |
| PCB | £0.50 | £0.50 | |
| Assembly | £0.50 | £0.50 | |
| Misc | £0.80 | £0.66 | |
| Total | £8.83 | £7.21 | |
| % target | 221% | 361% |