Experimental Characterization of Li-ion Battery cells for Thermal Management in Heavy Duty Hybrid Applications
2017
The performance and lifetime of lithium ion (Li-ion) batteries are highly dependent
on the internal operating temperature which makes thermal characterization
of battery cells necessary. Therefore, the main focus of this thesis work was to characterize
pouch and prismatic Li-ion cells by designing and conducting experiments
to measure thermal parameters. The specific heat capacity was quantified as well
as the heat conductivity in three dimensions. In addition, the heat generation from
the cells was measured for different load cycles. Subsequently, the determined thermal
parameters were inputs in a simulation model to determine the internal peak
temperature of the cell during different load cycles.
The experiments were carried out by using a custom-designed isothermal heat conduction
calorimeter (IHC). This calorimeter was modified for measurement of individual
thermal parameters. The modified setup was verified using available sample
materials and subsequently applied for measurements on the Li-ion cells. The heat
generated within the cells was measured for constant current rates and a dynamic
operation cycle.
The through-plane thermal conductivity for the provided pouch cell was measured
to be lower than the in-plane (0.7Wm−1 K−1 compared to 20-30Wm−1 K−1). In
addition, the specific heat capacity was measured to be 1100 J kg−1 K−1 for a
pouch cell and a prismatic cell. Lastly, the heat generated by the cells was measured
between 10mW to 30W.
To conclude, the heat generation and specific heat capacity was measured successfully
for both the pouch and prismatic Li-ion cell. The methods for thermal conductivity
in through-plane and in-plane were utilized for the pouch cell. However,
the proposed methods for thermal conductivities were found to be inapplicable for
prismatic cells due to the conduction through the aluminum casing. Nevertheless,
this opens up opportunities within the thermal characterization of Li-ion batteries.
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
0
References
3
Citations
NaN
KQI