California 6.1 Electrical Overview

[dspuk]

The 80% SOC is absolutely driven by emissions, the various formal emissions drive cycles (WLTP for most markets) that the emissions are measured over benefit significantly from the target only being 80%, it reduces the amount of time the alternator is operating during the cycle also in the most efficient battery absorption zone. The 80% allows enough head room to allow regenerative charging when you lift off. Both of these reduce measured CO2 and overall fuel consumption.

I want to clarify my earlier point — I wasn't disputing that emissions are a factor, rather that I wouldn't characterise the reasoning as 'eco nonsense.' My understanding is that the primary reason for the 80% charge limit is battery longevity, and the environmental benefits — reduced recycling, lower maintenance, and so on — flow naturally from that as secondary advantages.

If there's a document that suggests otherwise, I'd genuinely welcome you pointing me to it. From what I can find, a quick search returns five commonly cited reasons for the 80% limit, none of which are primarily eco-driven. In my view, the environmental upside is a welcome benefit of good battery management, rather than the driving rationale behind it.

Note - I used Claude to make this answer much politer.

 

[vbk1975]

I want to clarify my earlier point — I wasn't disputing that emissions are a factor, rather that I wouldn't characterise the reasoning as 'eco nonsense.' My understanding is that the primary reason for the 80% charge limit is battery longevity, and the environmental benefits — reduced recycling, lower maintenance, and so on — flow naturally from that as secondary advantages.

If there's a document that suggests otherwise, I'd genuinely welcome you pointing me to it. From what I can find, a quick search returns five commonly cited reasons for the 80% limit, none of which are primarily eco-driven. In my view, the environmental upside is a welcome benefit of good battery management, rather than the driving rationale behind it.

Note - I used Claude to make this answer much politer.

I am more than happy for you to hold a different view, generically these systems and how they work and why are operate the way they do are covered by "Electrical Energy Management Systems" AKA EMS or EEMS. A lot of the history dates back to 2012, AGM batteries got introduced at the same time to counter the effects of only charging to 80% SOC and Stop-Start on battery life and reduced usable capacity. Most of the comprehensive documents are paid for services, Bosch handbook also outlines the operation, but this is expensive.

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