12v voltage regulator inside canister

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Hi guys,

I want/prefer a stable 12V for powering a heated vest & gloves (about 100W ). I've got a Halcyon Pro 14 canister with plenty room for a batterypack, bms and a dc dc converter.

I'm thinking about using a synchronous switching step-down voltage regulator like the Pololu 12V, 15A Step-Down Voltage Regulator D24V150F12 (~50$)

View attachment 642583

Pololu 12V, 15A Step-Down Voltage Regulator D24V150F12

Using a 5S or 6S batterypack should give quite good efficiency aound 93% at ~8-9A (according the spec sheet).

View attachment 642584

Has anyone experience in using a switched converter in a (large) canister. I'm worried about the heat generated by the regulator inside a closed canister. I'm not sure how good Delrin is conducting heat away to the (cold) water outside the canister.
Mount a heatsink on the outside of the canister with a seal screw, then glue the MOSFET case with heatsink glue inside the canister. Problem solved.
upload_2021-2-18_8-52-43.jpeg
 
Thanks for all suggestions and tips guys. I did some measurements and I'm able to fit a LiFePO4 4S14P = 56 cells pack inside my Pro14 together with a BMS. This translates into a 300WH pack. With a nominal voltage of 12.8V this is ~24A and good enough to power a vest and gloves for about 3 hours which was my goal. This pretty much eliminates the need for a voltage regulator.

The 12.8V is very close to the 12.6V of a fully charged standard Li-ion pack so this should not be a problem even with the Santi vest which states '12V only' in the manual.

I think i'll go with either a Pitkin or Scaleo controller to take the heat down a bit when needed.
 
please remember with the voltage thing, they are saying 12v only so people don't put them on 4s lipo packs which are 14.8v nominal with a full charge just shy of 17v. These things are however designed to be used in motorcycle applications where the alternators are putting out 13.6-14v, so that is their actual designed voltage for the panels.
 
I just did the math on 12V vs 16,8V with a 55W / 12V santi vest. With 12V and resistance of 2,6 Ohm it will output 55W drawing 4,6A. Plugging in 16,8 it goes to 108W drawing 6.46A. That will hurt! :gas:

The heating wire will probably do some self current limiting I guess but still way to warm.
 
nominal voltage for LiFePO4 4S= 4*3,3V= 13,2V and max 4*3,6V= 14,4V but this would be managed by BMS (end of charge )

Santi vest is limited to 55W means 4,1A and the same time with max temp of 45°C !

attery running time:
SANTI 6Ah: 1h15min ~ 1h30min of heating,
SANTI 24Ah: 5 ~ 6h of heating

Total power of connected devices cannot exceed 200W. Those devices must be designed to be powered with 10.8-12V input.
---------------------------------------------------------------------------------
if you look THEIR l : battery spec

  • capacity: 24 Ah,
  • operating voltage: 11,1 V,
  • cells type: Li-Ion
you can switch on 3S and more P .

PS : you have these SANTI connectors or china replicas ?
 
I recently built another cannister for a friend using the same mini pwm dimmer I built for my own.
Using LG 21700 batteries, a nice 35Ah, max 400W, dual output.
The pww dimmer uses a ATTiny85, combined with some resistors and a n-mosfet. Simple program that adjusts between user selectable 100%/75/50/25 flicking on/off power
The santi connectors are made by chogori, used to find on aliexpress but no luck recently..
 

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