Go Back   EcoModder Forum > EcoModding > EcoModding Central
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 02-08-2024, 06:02 AM   #1 (permalink)
48V
EcoModding Lurker
 
Join Date: Mar 2021
Location: NC
Posts: 6
Thanks: 1
Thanked 0 Times in 0 Posts
16.8v on a 12v starter?

I have a Silverado (5.3L) that I am installing a large 48v electrical system in, to power most belt drive accessories. One of the major things I want to do is get rid of that giant lead battery!

Now, let's say I replace the starter battery with a 4 cell lithium ion battery? That's 16.8v vs 12 or less. It would not power anything else, I don't want 16 volts for anything else. Nothing but starter.

Is this going to damage a typical 12v American style starter motor? I know they sell 14 and 16 volt lead acid batteries for racers, and they claim it works fine, but is that true? It would not be the end of the world, starters are cheap and easy to replace, but I don't want to get stranded somewhere.

I might just try to leave the battery at 16.0v, not quite as hot and that way I don't have to float charge the lithium battery at max voltage.

I could use a 12.6v 3 cell, or 14.4v Lifepo4 batteries instead, but I would like it to crank super fast.

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 02-08-2024, 10:25 AM   #2 (permalink)
Somewhat crazed
 
Piotrsko's Avatar
 
Join Date: Sep 2013
Location: 1826 miles WSW of Normal
Posts: 4,017
Thanks: 460
Thanked 1,096 Times in 967 Posts
For starters, the spec used to be 14.8v for charging batteries in very cold weather. In theory therefore most electronics should tolerate that and more, but in reality it varies case by case. My glowplug relay which is solid state has a limit of 14.6 stamped on it and I know from experience replacing said relay that 14.7 fails the relay.

The starter will draw more current, spin faster and develop more hp (maybe now 3 1/2). The brushes will arc more and live shorter lives but that shouldn't be noticable. I overvolt my traction motor significantly and know of someone that has doubled his traction system voltages to 400 volts on a 48v rated motor. The trick will be isolating the other systems from the 16 volts and the bemf produced
__________________
casual notes from the underground:There are some "experts" out there that in reality don't have a clue as to what they are doing.
  Reply With Quote
The Following User Says Thank You to Piotrsko For This Useful Post:
48V (02-08-2024)
Old 02-08-2024, 01:54 PM   #3 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 27,422
Thanks: 7,698
Thanked 8,522 Times in 7,012 Posts
Throw in a resistor in series.
__________________
.
.
Without freedom of speech we wouldn't know who all the idiots are. -- anonymous poster

____________________

History is a warning for the future -- Dr. John Campbell
  Reply With Quote
Old 02-08-2024, 03:17 PM   #4 (permalink)
High Altitude Hybrid
 
Join Date: Dec 2020
Location: Gunnison, CO
Posts: 1,924

Avalon - '13 Toyota Avalon HV
90 day: 40.45 mpg (US)

Prius - '06 Toyota Prius
Thanks: 1,022
Thanked 529 Times in 426 Posts
Quote:
Originally Posted by freebeard View Post
Throw in a resistor in series.
And put it in the intake to heat the incoming air.
__________________
  Reply With Quote
Old 02-08-2024, 05:03 PM   #5 (permalink)
48V
EcoModding Lurker
 
Join Date: Mar 2021
Location: NC
Posts: 6
Thanks: 1
Thanked 0 Times in 0 Posts
Quote:
Originally Posted by Piotrsko View Post
For starters, the spec used to be 14.8v for charging batteries in very cold weather. In theory therefore most electronics should tolerate that and more, but in reality it varies case by case. My glowplug relay which is solid state has a limit of 14.6 stamped on it and I know from experience replacing said relay that 14.7 fails the relay.

The starter will draw more current, spin faster and develop more hp (maybe now 3 1/2). The brushes will arc more and live shorter lives but that shouldn't be noticable. I overvolt my traction motor significantly and know of someone that has doubled his traction system voltages to 400 volts on a 48v rated motor. The trick will be isolating the other systems from the 16 volts and the bemf produced
Perfect, just wanted to know it won't instantly let out the magic smoke. I haven't decided entirely how I want to wire it up, but yeah, it will be annoying isolating the voltage everywhere, even the starter solenoid.

The 16v will charge off the main 48v battery and I could adjust the voltage of a 4S pack down by simply by not charging them all the way. Probably smarter in the long run, I'm basically just using the high output batteries like a capacitor, they don't need to hold many watts.

Then to complicate it even more I'll have a 100A 13.8v converter to replace the alternator and power everything else 12v. I could probably use the 16, it just kind of scares me with so many electronics on the engine these days that I don't even understand...

Eventually I'd like to add a motor to the main engine pulley, and be able to use it as a starter/generator...but I'm getting ahead of myself.
  Reply With Quote
Old 02-09-2024, 02:22 PM   #6 (permalink)
Corporate imperialist
 
oil pan 4's Avatar
 
Join Date: Jul 2011
Location: NewMexico (USA)
Posts: 11,168

Sub - '84 Chevy Diesel Suburban C10
SUV
90 day: 19.5 mpg (US)

camaro - '85 Chevy Camaro Z28

Riot - '03 Kia Rio POS
Team Hyundai
90 day: 30.21 mpg (US)

Bug - '01 VW Beetle GLSturbo
90 day: 26.43 mpg (US)

Sub2500 - '86 GMC Suburban C2500
90 day: 11.95 mpg (US)

Snow flake - '11 Nissan Leaf SL
SUV
90 day: 141.63 mpg (US)
Thanks: 269
Thanked 3,515 Times in 2,790 Posts
Run it, you won't hurt it.
Race cars have ran 7 cell lead acid batteries for ever.

__________________
1984 chevy suburban, custom made 6.5L diesel turbocharged with a Garrett T76 and Holset HE351VE, 22:1 compression 13psi of intercooled boost.
1989 firebird mostly stock. Aside from the 6-speed manual trans, corvette gen 5 front brakes, 1LE drive shaft, 4th Gen disc brake fbody rear end.
2011 leaf SL, white, portable 240v CHAdeMO, trailer hitch, new batt as of 2014.
  Reply With Quote
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com