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Discussion Starter #1
Interesting video, these guys use math to determine if EV's see their weight fluctuate as they go from fully to not charged...

 

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Spoiler: So you do go faster as you use up more battery power.

Seems very MythBusters to me. Thanks for posting.
 

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The answer is basically no.

The chemical battery cell moves electrons away from the donor element (Lithium in the Bolt EV) and holds the free Lithium ions in place, forming an electrical field between the electrodes, which creates an electrostatic pressure, and that is Voltage. There is no gain nor loss of any material in a Lithium-Ion cell. But overcharging can cause ion migration and generate heat. The heat can cause any other materials to release some gas, and Hydrogen if water is present from electrolysis. So a correctly charged cell will not change its weight, but will gain energy which is weightless. This is like a metal spring that can gain energy when stretched, but the spring weight never changes.
 

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Discussion Starter #4
The answer is basically no.

The chemical battery cell moves electrons away from the donor element (Lithium in the Bolt EV) and holds the free Lithium ions in place, forming an electrical field between the electrodes, which creates an electrostatic pressure, and that is Voltage. There is no gain nor loss of any material in a Lithium-Ion cell. But overcharging can cause ion migration and generate heat. The heat can cause any other materials to release some gas, and Hydrogen if water is present from electrolysis. So a correctly charged cell will not change its weight, but will gain energy which is weightless. This is like a metal spring that can gain energy when stretched, but the spring weight never changes.
thanks for the explanation ray! Like the video said, perhaps about equivalent to the weight of a grain of sand ;)
 

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Great explanation Raymond, at least with weight not changing it's one less thing we have to worry about with what will impact range.
 

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Thanks to both. I am an EE with ten years of teaching experience (and had excellent grades in Chemistry), over 40 years working with computers (I started when they used transistors in 1972), and over 50 years playing with batteries and electronics. So it is natural to me to explain how technology works in simple terms.

I am expecting to buy an GM produced EV (either a BEV such as the Bolt or even a simple hybrid) and get off burning gasoline. My signature explains my dedication, having a working and registered Level 2 EVSE but no EV.
 

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Thanks to both. I am an EE with ten years of teaching experience (and had excellent grades in Chemistry), over 40 years working with computers (I started when they used transistors in 1972), and over 50 years playing with batteries and electronics. So it is natural to me to explain how technology works in simple terms.

I am expecting to buy an GM produced EV (either a BEV such as the Bolt or even a simple hybrid) and get off burning gasoline. My signature explains my dedication, having a working and registered Level 2 EVSE but no EV.
Thankful for that, I bet it could have gotten really technically, turning out to be some different language to us :D
 
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