Test: Alternator vs. no alternator = 10% MPG gain @ 70 km/h

[JackMcCornack]

Gosh, great minds and all that. My latest MAX Update for the Mother Earth News web site has my observations on headlight fuel consumption (originally titled "Liquid Light" but changed by the editors so's the muggles could figure it out). One thing's for sure; the better your mileage, the more significant electrical loads become.

MAX Update No. 86: How Headlights Affect MPG

[moonmonkey]

where did u guys buy your li-ion car battires?

[oil pan 4]

Originally Posted by deathtrain

what battery are you using? and you using it for craking and running?

http://ecomodder.com/forum/showthrea...ies-18547.html

[Ladogaboy]

Originally Posted by moonmonkey

where did u guys buy your li-ion car battires?

The best information on that state-side would be in the EV forums. Most of these batteries tend to be made in China and sold by distributors here. I haven't kept up on the current market, so I'm probably no good to you.

Another thing to consider is (for cost purposes), you'll probably want to build your own battery... usually 4 Li cells, a low voltage cutoff, battery monitoring system...

[brucepick]

Headlights.

You guys running with alternator disabled - can you run with headlights on for 3 hours?

I have some likely solutions to that but want to see if anyone else has solved it already for their own vehicle.

[oil pan 4]

Originally Posted by Ladogaboy

Most of these batteries tend to be made in China and sold by distributors here.

My battery was made in the USA.

Originally Posted by brucepick

Headlights.

You guys running with alternator disabled - can you run with headlights on for 3 hours?

I have some likely solutions to that but want to see if anyone else has solved it already for their own vehicle.

55 watts for each head light for 3 hours, that is about a third of a kilowatt hour.
I am not even going to try that.

[Ladogaboy]

Originally Posted by oil pan 4

My battery was made in the USA.

I'm going to go out on a limb and guess that those Li cells were built in China; and you are paying for someone in TN to assemble the battery for you. I couldn't see where they stated on their site that they actually construct the Li cells, and under their FAQ, they only state that they use copper and lead terminals in the "construction" of the batteries.

Regardless, I was referring to the purchase of the Li cells with which a person could construct a 12v battery, and those (in my experience) mostly are made in China. I think even CALB/Sky batteries are, but they have a distribution warehouse within driving distance of me. *shrug*

[deathtrain]

most people don't have the skill to just build one. and almost everything is made in china no a days.

[oil pan 4]

My battery came from florida.
I cant find any lithium batteries that are identical to the ones used in my pack. I found lots of cheaper looking chinese copies.

If they are chinese cells then I will just construct my own lithium starting batteries with chinese cells for roughly 50% or less more than the cost of a good flooded lead acid starting battery.

[brucepick]

Originally Posted by brucepick

Headlights.

You guys running with alternator disabled - can you run with headlights on for 3 hours?

I have some likely solutions to that but want to see if anyone else has solved it already for their own vehicle.

Not even a peep of interest in this topic?

My headlight bulbs were made in India; that may be of interest to this discussion.

Yes you can save a bunch of weight by substituting a lithium-based pack for the old lead acid battery. Weight savings is mostly helpful in acceleration contests and kind of helpful in city driving.

Now when you spend up to half your time coasting with engine off, and you want to drive more than 20-30 minutes, what's going to happen with that lithium pack? If you don't recharge it your range is limited. If you do run the alt, you're missing the gain that is the core topic of this thread: improved mpg by not running the alternator.

And furthermore, how are you going to run headlights, long term? Granted, folks in warm climates don't drive in the dark as much as we Northerners do. In winter I commute an hour+ each way in the dark. My calcs indicate I'd need about 38AH of stored power just to run my headlights (plus a few other minor items) for 3 hours, if I don't recharge the battery that powers them while driving. In this, I'm not considering the power needed to run the car itself; i.e. computer, fuel pump, ignition, etc.

I think it's a question that needs to be considered.