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Luno · 06-04-2018, 03:45 PM

I should introduce myself better as a new member, but I have been a mental subscriber to Ecomodder for a decade, trying out most advise only short of a full belly pan and a Kammback, never caring about giving anything back to the community, sorry! However I've "invented" a new mod, not mentioned here I would like to share: I do a lot of city driving and noticed than when my alternator kicks in, my steady 35mph consumption goes up from 98mpg (2.4L/100km) to 70mpg (3L/100km) and my idle goes from 0.6L/h to 0.9L/h (I'm European, trying to mix empirical units with ISO units for this international audience), so an alternator delete is a logical next step, but I don't wan't to carry additional AH to make up for the missing charging, as the weight penalty will cost dearly in stop and go traffic, so here is my Hi-tech solution: Loosing the 40AH battery saves 16 pounds, replacing it with a 4S5P Li-ion pack, the size of a grown man's fist. The observant reader have noticed that this gives me a 16V car electrical system, but in reality it is a 15V system as I only charge each cell to 3.9V for a long cyclic life and safety as only float charging at 70% charged is safe with Li-ion. My car works perfectly on this, no fried coil or bulbs or any error codes. I did check with my workshop manual and 16V is within specs. Such a pack does not start my car so I added a super capacitor bank in parallel over a shunt resistor to take care of this. However, all this does not save me anything besides weight, so I've added a 50W solar panel and a 15V charger to keep my battery and capacitor above the 14.45 my alternator would like to push, so it shuts down. 50W solar on the dashboard is too puny for low beams, but they are only on at night where the sun doesn't shine anyway, so I got plenty for systems and DRL and my power windows are really fast!! This saves me guestimated 0.8L /tank idling and around 25% in city driving in the daytime, which both are substantial savings, that avoids the extra bettery weight and plug-in charging and does not require unbelting the alternator so quite unintrusive. It could even be build into a battery sized box with two wires going to the solar panel, and be a simple battery swap procedure to install and un-install.

06-04-2018, 03:45 PM	#1 (permalink)
Luno EcoModding Lurker Join Date: Jun 2018 Location: Denmark Posts: 5 Thanks: 0 Thanked 8 Times in 3 Posts	Virtual alternator delete. I should introduce myself better as a new member, but I have been a mental subscriber to Ecomodder for a decade, trying out most advise only short of a full belly pan and a Kammback, never caring about giving anything back to the community, sorry! However I've "invented" a new mod, not mentioned here I would like to share: I do a lot of city driving and noticed than when my alternator kicks in, my steady 35mph consumption goes up from 98mpg (2.4L/100km) to 70mpg (3L/100km) and my idle goes from 0.6L/h to 0.9L/h (I'm European, trying to mix empirical units with ISO units for this international audience), so an alternator delete is a logical next step, but I don't wan't to carry additional AH to make up for the missing charging, as the weight penalty will cost dearly in stop and go traffic, so here is my Hi-tech solution: Loosing the 40AH battery saves 16 pounds, replacing it with a 4S5P Li-ion pack, the size of a grown man's fist. The observant reader have noticed that this gives me a 16V car electrical system, but in reality it is a 15V system as I only charge each cell to 3.9V for a long cyclic life and safety as only float charging at 70% charged is safe with Li-ion. My car works perfectly on this, no fried coil or bulbs or any error codes. I did check with my workshop manual and 16V is within specs. Such a pack does not start my car so I added a super capacitor bank in parallel over a shunt resistor to take care of this. However, all this does not save me anything besides weight, so I've added a 50W solar panel and a 15V charger to keep my battery and capacitor above the 14.45 my alternator would like to push, so it shuts down. 50W solar on the dashboard is too puny for low beams, but they are only on at night where the sun doesn't shine anyway, so I got plenty for systems and DRL and my power windows are really fast!! This saves me guestimated 0.8L /tank idling and around 25% in city driving in the daytime, which both are substantial savings, that avoids the extra bettery weight and plug-in charging and does not require unbelting the alternator so quite unintrusive. It could even be build into a battery sized box with two wires going to the solar panel, and be a simple battery swap procedure to install and un-install.