Quote:
Originally Posted by mpg_numbers_guy
Going to have the ground straps inspected today. The guy who will be working on the Insight has graciously allowed me to be there to see how he does everything. Should be a good learning experience.
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The ground straps are simple copper wires that connect the engine (and IMA motor) to the frame of the car. The engine sist on rubber mounts and is not grounded (without these straps) to the frame of the car. If the copper wires get corroded, all sorts of awful electrical problems ensue. You can have IMA system problems, the engine can misfire, you might find that the DC-DC converter shuts off or your cluster does weird things.
Quote:
Originally Posted by mpg_numbers_guy
How complicated and expensive was your supercapaciter/lithium battery setup? If it's fairly complicated, is there a simpler way to do a lithium battery without spending $700 for one off of Amazon?
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The supercapacitors would be mostly unnecessary if you don't plan to start the car with them, and only ever start using the hybrid pack. Be aware that the Insight will not start from the hybrid pack if temperature outside drops below 0F as this can be dangerous for NiMH cells. However this is doubly true of lithium, so if the car will ever sees subzero temps, you realistically should not use a lithium battery. EVs which have lithium batteries will run a resistive heater to keep the batteries above freezing, but if left in the cold too long without charging the batteries run dead from trying to stay warm.
Normal lead acid batteries are pretty durable and would not be destroyed if attempting to use them below freezing (dangerous for lithium) or subzero (dangerous for NiMH).
LiFePO4 is the "safe" lithium chemistry, which won't catch on fire. Lithium Ion is the unsafe one which is lighter, has higher capacity, and can suddenly burst into flames if you're not very careful with them.
The supercapacitors in my car are to handle the starting and transient loads of running the car. The lithium (LiFePO4) battery is just a backup, in case I leave my lights on or want to run the radio for a while with the car off.
You can make your own inexpensive lithium pack with 4 of these:
https://www.ev-power.eu/LiFePO4-smal...e-CE.html#tab2
^ This *may* start the car fine in good weather but low temperatures or repeatedly using the 12v starter would be hard on a lithium battery this small.
BatterySpace sells already-assembled packs similar to using 4 of the above cells, for a small premium - $133 for the battery, or $189 for the same battery but with a balancing circuit and some other safeguards inside.
https://www.batteryspace.com/lifepo4...assed-dgr.aspx
I probably wouldn't pair just supercapacitors with the IMA system, as when the car goes into auto-stop it needs a fairly long lasting 12v battery to keep all of the electronics running.