Project 1 Mechanical design of battery pack
Battery pack capacity: 18 kWh
Cell: ANR26650M1-B
Prepare a detailed battery pack drawing along with its enclosure. State your assumptions.
Cell: Specifications of the particular cell is as following. Datasheet attached herewith (LithiumWerks - Charging Recomendation Document 2021.pdf).
| ANR26650M1-B | |
| Nominal Ratings | |
| Battery Type | lithium iron phosphate |
| Voltage | 3.3 V |
| Capacity @ 25 ºC | 2.56 Ah +/- 0.1 Ah |
| Energy @ 25 ºC | 8.25 Wh |
| Speciic Power @ 25 ºC, 2 sec pulse | > 4000 W/kg |
| Impedance (1KHz AC) Typical | 6 mΩ |
| Cycle Life at 1C/1C, 100% DOD | > 4000 cycles |
| Discharging | |
| Max Continuous Discharge Current | 50 A (20C rate) |
| Max Pulse Discharge Current (10s) | 120 A (48C rate) |
| Minimum Voltage / HPPC Pulse | 2 V / 1.6 V |
| Temperature | -30 ºC to 60 ºC |
| Charging | |
| Recommended Charge Current | 3 A (1.2C rate) |
| Max Continuous Charge Current | 10 A (4C rate) |
| Max Pulse Charge Current (10s) | 20 A (8C rate) |
| Float Voltage | 3.45 V |
| Recommended charge V & Cut-off Current | 3.6 V, taper to 125mA |
| Temperature Range (reduce charging current to 250mA when under 0 ºC) | -20 ºC to 60 ºC |
| Storage | |
| Storage Temperature | -40 ºC to 70 ºC |
| Mechanical | |
| Diameter | Ø25.96 +/- 0.5 mm |
| Length | 65.15 +/- 0.5 mm |
| Mass | 76 g +/- 1.0 g |
| Certiications | |
| Transportation | UN 3480 (UN38.3), CIQ |
| Safety | UL 1642, IEC 62133-2 |
| Environmental | REACH, RoHS, ISO-14001 |
| Quality System | TS/IATF-16949, ISO-9001 |
| Transportation | |
| Shipping | Via Air @ 30% SOC |
| Via Sea @ 50% SOC | |
Assume battery voltage required is 300 V. (We will follow specs for Mitsubishi i-MiEV, data shett attached hereith)
Battery designed will be of 300 V 60 Ah.
To achieve 300 V we will use 92 cells in series.
To achieve 60 Ah we will use 24 cells in parrallel.
Total cells required 1104 cells.
Individual cell dimension,
Cell topology will be as follows:
6 cells will be connected in parrallel to generate 3.3V 15 Ah block(block a).
4 of such blocks will then connected in parrallel to generate 3.3 V 60 Ah block(block b).
92 of such blocks will be connected in series to generate the required battery pack.
The batteries will be connected by pure nickel strips.
We will be using aluminium battery enclosures. They will be cheap, light.
https://www.novelis.com/automotive/electric-vehicle-battery-enclosure/