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Silver pack reassembled.
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some interesting observations
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After Ian's thorough cycling experiment, we reassembled the pack. While the pack was apart, we did a few more interesting test. 1. The positive temp coefficient band that passes through the side of each 6 cell subpack was removed in order to get some data about it's temperature response. Each 6 cell strip measures 1.5 ohm when at room temp. It raises to 2 ohms at about 135F, and is 4 ohms @ 160F.
2. The 180 ohm "resistors" that are in each of the 10 monitor lines feeding to the BCM, are also positive temp coefficient devices. They act like self resettable thermal fuses, as their resistance goes into the K ohm range when they get hot, and returns to 180 ohms when cool.
3. The battery end studs are either a square (+), or a hex (-), and the orange connection plate has mating sockets, so it is virtually impossible to assemble the pack wrong.
When the pack was assembled, we dropped it back into the silver insight. The car had been having trouble cranking just before the pack was removed, but the recharged and cycled pack turned over the car and it started immediately,just as it should, even though the 12V battery had been out of the car for 2 weeks prior, so the computers were all reset, and the SOC showed zero. This means that the car must do a HV pack voltage check before it decides to use it for cranking,even though it did not know the SOC. Once we saw the easy start, and no codes, we pulled Ian's pack, and after mounting his BCM and MCM on the silver cars pack, we installed it in his car, so he can watch it on his 500 mile/week commute. He will also test and cycle his subpacks, by exposing the two ends of the strings,to see how well balanced it is. We suspect that a pack must sit for a day or so to have the voltage settle to it's no load voltage,and show any imbalance? I also welded up a radiator mount for the Insight on a stand, and hope to get it running this week. Another fruitful Sat. Graphs of the battery pack initial conditions, as well as Ians pack initial conditions: Ian's Graphs
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