Smallest starter battery

Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
BlueJ currently has a single battery (group 27) for both house and starting. Thinking about adding a dedicated start battery. Diesel is Volvo-Penta MD2010 two cylinder. Motor has glow plugs and starts well in all temps.

What's a reasonable size? Would like to be on the small side due to weight. More specifically, I was wondering if a small garden tractor battery would work instead of the standard group 24.
 
Last edited:
Oct 29, 2016
1,915
Hunter 41 DS Port Huron
I would love to be on the small size to, due to weight, but the older I get the more weight I seem to have, funny how that works, oh you are talking batteries.......sorry
 
  • Like
Likes: jssailem

Gunni

.
Mar 16, 2010
5,937
Beneteau 411 Oceanis Annapolis
Your engine manual should specify an Amp-hour rating for the starter battery, then you can apply that risky-racer factor, cut the capacity by 0.3, shave some weight off the battery cables by going down a size, tie it down with 1/8" amsteel to titanium padeyes and go out there and Win! :)
 
  • Like
Likes: Jackdaw
Feb 6, 1998
11,665
Canadian Sailcraft 36T Casco Bay, ME
BlueJ currently has a single battery (group 27) for both house and starting. Thinking about adding a dedicated start battery. Diesel is Volvo-Penta MD2010 two cylinder. Motor has glow plugs and starts well in all temps.

What's a reasonable size? Would like to be on the small side due to weight. More specifically, I was wondering if a small garden tractor battery would work instead of the standard group 24.
Odyssey PC925, PC1100 or PC1200...

Here's a PC1200 next to two G-31's..

 
Sep 20, 2014
1,320
Rob Legg RL24 Chain O'Lakes
Since we all know you are a glutton for technology, why not go with Li-iron? There are a few motorcycle battery manufacturers who are offering LiFePO 4. They are able to handle massive amounts of current draw without significant degradation. They also tolerate standard charging systems.
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Since we all know you are a glutton for technology, why not go with Li-iron? There are a few motorcycle battery manufacturers who are offering LiFePO 4. They are able to handle massive amounts of current draw without significant degradation. They also tolerate standard charging systems.
That has occurred to me. I'd love to her of anyone that has done this in a sailboat. I'm not interesting in being the first!
 
Jan 4, 2010
1,037
Farr 30 San Francisco
I saw on the youtube a video of somebody starting their VW TDI in Quebec City in the winter -40 using 4 A123 cells the size of your fist. LiFePO.

Ocean energy has lots of expensive solutions for you! Also there are capacitive based systems, you trickle charge a big cap (but light I think) then you can crank for a min or so after which you are locked out for a few min. Think that was Maxwell (was for diesel truck start stop system) bout $1k I could have got all the details confused however!