Quote:
Originally Posted by meelis11
brucepick - here is one idea. Why not use voltage booster circuit instead of 1.2V D-cell pack?
AutoSpeed - Voltage Booster, Mark II
Just buy one voltage step-up converter per-headlight (so you dont stress 150W max circuit too much - probably can stay with passive cooling that way too), tune your voltage to 14V and you dont have to deal with Nimh booster pack anymore. |
Thanks, meelis11.
I think that currently, that solution is well worth considering.
I looked at DC-DC converters similar to the one you linked to, but at the time that I built the booster pack - summer 2014 - the voltage converters I found were limited to 10A capacity. LED headlights weren't really feasible yet either, so I would have needed approx 20A capacity just to handle high+low beams plus smaller bulbs. And that would have left the fans running on puny 12V, which is tolerable but not ideal.
So I built the 1.2V booster pack in summer 2014 and it served me well that winter. Winter requires far more headlight use, and not just as DRLs so I can be seen. I need to see the road ahead in the dark.
The 8 D-cells are rated 10AH each, and I'm confident they can safely be discharged at 2C rate. That's 20A each, or 160A combined as they are in parallel. I won't exceed that, and could probably run the starter motor from the boosted deep cycle batteries info need to!
My pack supports everything running off the lead acid deep cycles - lights and fans + wipers. If I were to switch to a DC-DC converter instead, I'd need several to properly support all those circuits. And I would not need to recharge the NiMH pack.
Down side:
Likely approx 90-92% efficiency of the converter. That would come into play on days when I use more than 40% of my battery capacity, driving usage past 50% which tends to reduce the life of the lead acid batteries.