Project 1 Mechanical design of battery pack
AIM :
To prepare and develope a battery pack of 18KW using ANR26650M1-B cells .
THEORY :
(Which refered from the online )
A123's high performance nanophospate lithium iron phosphate (lifepo4)battery technology delivers high power and energy density combined with excellent safety performance and extensive life cycling in a lighter weight more compact package .our cellls have low capacity loss and impedance growth over time as well as high usable energy over a wide state of charge (soc) range allowing our systems to meet end of life power and energy requirments with the ,imimal pack oversizing .
commercial solution :
Datacenter ups.
Telecom backup .
It backup.
Autonomously guided vehicles (agv).
Medical devices .
Government solutions :
Military vehicles
Military power grid
Soldier power
Grid solution :
Frequency regulation
Renewables integration
Reserve capacity
Transmission and distribution
Transportation solution :
Hybrid , plug in Hybrid ,
commericial vehicles
off - Highway vehicles
passenger vehicles
ANR26650M1-B Technical data:
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Cell Dimensions
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26 x 65 mm
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Cell Weight
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76 g |
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Cell Capacity (nominal/minimum) (0.5C Rate)
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2.5/2.4 Ah
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Voltage (nominal)
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3.3 V |
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Internal Impedance (1kHz AC typical)
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6mΩ
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| Power |
2600 W/kg
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Recommended Standard Charge Method
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2.5A to 3.6V CCCV, 60 min
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Recommended Fast Charge Method to 80% SOC
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10A to 3.6V CC, 12 min
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Maximum Continuous Discharge
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50 A |
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Maximum Pulse Discharge (10 seconds)
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120 A |
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Cycle Life at 20A Discharge, 100% DOD
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>1,000 cycles
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Operating Temperature
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-30°C to 55°C
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| Storage Temperature |
-40°C to 60°C
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About cell:
The LithiumWerks ANR26650M1-B is the next generation of A123 Systems' pioneering 26650 cylindrical cell, now with greater power and energy density and lower impedance. This versatile lithium ion cell is suitable for a wide variety of applications and system designs.
About module:
A battery management system (BMS) is any electronic system that manages a rechargeable battery (cell or battery pack), such as by protecting the battery from operating outside its safe operating area, monitoring its state, calculating secondary data, reporting that data, controlling its environment.
About Battery pack:
A battery pack is a set of any number of (preferably) identical batteries or individual battery cells. They may be configured in a series, parallel or a mixture of both to deliver the desired voltage, capacity, or power density.
CALCULATION :
To determine the space and cell need to havee the 18kw .
Cell energy = Nominal voltage * niminal cell capacity
cell energy = 3.3*2.5
= 8.25wh
cell volume = pi *r*r*h
=3.140.0130.065
=0.0344929 m^3
Now find the watt per volume the cell can produce :
cell energy density = cell energy / cell volume
=8.25/0.0344929 wh/m^3
=239.17 wh/m^3
now desing the battery pack .
to get 18kw battery pack
let us consider 58 cells are connected in series a and 38 cells connected in parallel .
voltage pack = nominal voltage * cell connected in series
=3.3 * 58
=191.4
current capacity of the battery pack = cell capacity * cells conned in parallel
=38*2.5
=95ah
the total energy of the battery pack = voltage * current capacity
= 191.4*95
= 18.18kw