Maxim & SparkSister
Maxim Maxim
SparkSister SparkSister
SparkSister SparkSister
Hey Maxim, I've been tinkering with a new battery pack that can boost a car's starter on a jump, but I'm trying to make it super reliable—any ideas on how to structure the circuit so it stays safe even if the battery hiccups?
Maxim Maxim
Sure thing. Keep it simple and safe. Use a dual‑cell or three‑cell pack wired in series so you stay at the starter voltage, but add a robust battery management IC that watches for over‑current, over‑voltage, and temperature. Add a high‑current fuse or circuit breaker on the output and a manual disconnect switch so you can kill the pack fast if something goes wrong. For the actual jump, a MOSFET or solid‑state relay with a built‑in over‑current lockout will let you tap the starter rail while keeping the battery isolated when it’s not in use. Finally, put a diode or small DC‑DC converter to keep the pack at a steady voltage and keep the car’s electronics happy. That way if the battery hiccups, the rest of the system stays protected.
SparkSister SparkSister
Thanks for the solid rundown, Maxim—sounds like a proper skeleton for a jump‑starter. I’ll grab a BMS that doesn’t care about the manual and see if I can jazz up the MOSFET with a little over‑current dance of my own. Maybe a bit of that old wiring diagram I’ve got in my drawer will let me sneak in a spark or two. Will let you know if the pack starts doing the cha‑cha.
Maxim Maxim
Sounds like a plan. Just keep the MOSFET gate drive clean, and make sure the fuse rating is a bit higher than your max jump current but not so high that it won't trip in a fault. If you start to see any odd behavior, pull the disconnect and double‑check the BMS data. Let me know how the cha‑cha goes.
SparkSister SparkSister
Sounds good—will keep that gate drive tight and pick a fuse that’s just shy of my max jump current. Will pull the disconnect if anything funky pops up and double‑check the BMS data. I'll hit you back with the cha‑cha update once I’ve run the first test.
Maxim Maxim
Nice, keep it tight and test it in a controlled environment. Hit me back when you’ve got the first run—happy to see it dance.
SparkSister SparkSister
Will do—test in a safe space first and keep that circuit tight. Ping you when it’s ready to dance.
Maxim Maxim
Sounds good, looking forward to the update.