Li-Ion battery is famous for energy density and longevity. Battery cells, furthermore, are one of the...

 

 

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Li-Ion battery is famous for energy density and longevity. Battery cells, furthermore, are one of the most expensive components of the e-scooter. The combination of lithium-ion chemistries that involve the lithium ion with delicate manufacturing process occasionally leads to defective battery cells that have little or zero energy storge capacity. When assembled with some other good battery cells in a battery pack, the defective battery cells compromise the overall output voltage and increase the risk of malfunction. In order to reduce the number of battery packs installed with defective battery cells, XtraSonic randomly samples 10 units of XFactor, one of the bestselling battery packs (each comprising 15 batteries in series), every day to seek for defective battery cells. Meanwhile, XtraSonic has provided data from 14 days of benchmark production and intends to prepare quality control chart(s) with the control limits based on the data. Furthermore, the manager in the department of quality control wants to see recent sample data from the last 14 days plotted against the control limits calculated from the benchmark production data. Benchmark Production Day 1 2 3 4 5 6 7 8 9 10 11 12 5 11 13 3 5 14 8 4 Calculate the relevant control limits and prepare relevant quality control chart(s) using z = 3. Provide an analysis of their performance over the past 14 days. (Show all work for full marks and use 4 decimals for standard deviation and control limit values) # of Defective Battery Cells 3 5 6 4 3 4 2 6 4 1 4 Recent Production Day 1 2 3 4 5 6 7 8 9 10 11 12 13 14 # of Defective Battery Cells 4 5 4 2 4 3 4 7 2 4 4 Li-Ion battery is famous for energy density and longevity. Battery cells, furthermore, are one of the most expensive components of the e-scooter. The combination of lithium-ion chemistries that involve the lithium ion with delicate manufacturing process occasionally leads to defective battery cells that have little or zero energy storge capacity. When assembled with some other good battery cells in a battery pack, the defective battery cells compromise the overall output voltage and increase the risk of malfunction. In order to reduce the number of battery packs installed with defective battery cells, XtraSonic randomly samples 10 units of XFactor, one of the bestselling battery packs (each comprising 15 batteries in series), every day to seek for defective battery cells. Meanwhile, XtraSonic has provided data from 14 days of benchmark production and intends to prepare quality control chart(s) with the control limits based on the data. Furthermore, the manager in the department of quality control wants to see recent sample data from the last 14 days plotted against the control limits calculated from the benchmark production data. Benchmark Production Day 1 2 3 4 5 6 7 8 9 10 11 12 5 11 13 3 5 14 8 4 Calculate the relevant control limits and prepare relevant quality control chart(s) using z = 3. Provide an analysis of their performance over the past 14 days. (Show all work for full marks and use 4 decimals for standard deviation and control limit values) # of Defective Battery Cells 3 5 6 4 3 4 2 6 4 1 4 Recent Production Day 1 2 3 4 5 6 7 8 9 10 11 12 13 14 # of Defective Battery Cells 4 5 4 2 4 3 4 7 2 4 4