The pack voltage suddenly dropped and two of the rear pack cells read zero volts. What is that lithium smell?
Full pack view, find the tip of the blue arrow.This is the rear pack, showing 20 of the 26 modules in the rear pack.
The third and fourth in the stack welded together.
We had an issue while removing the rear pack. To remove the rear pack from under the car where the gas tank had been you need to disconnect the electrical and BMS leads from the car. We built the pack with long conduit pigtails such that there are no connectors under the car to leak or get damaged. We then also place a solenoid in the pack housing to cut off the positive side of the battery from even the pigtail as an added precaution. We were told that was over kill. When removing the "dead" negative lead from the front of car connection we noted, "I think my finger is tingling?" " Can't be, the main fuses are pulled and the positive lead is disconnected." "OK, lets check with a meter." "The meter says nothing from POS to that connection, must be your finger." We finished removing the bolt and started to pull the cable from the housing, POW. Arc from the cable end (Which now needs to be replaced) to the battery case. "What the %#@^"
There was 110V from the cable to the chassis of the car. Is the POS solenoid stuck? No. BMS wires shorted? No. Main NEG cable crossed a bolt in the pack? No. One of the bus bars in the pack came loose? No. ..... When the battery failed, it internally shorted the entire rear pack to the chassis of the car! We did not know these batteries could fail this way, Thus it is imperative that a full system fuse be placed as close to the battery output terminals as possible. We got lucky as the method in which this system failed had no fuse in the failure path, all the fuses were placed up at the front of the car and after the pigtails for ease of accessibility.
The entirety of the failure was contained in the rear pack housing. There was much rejoicing.
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