The J/109 Class Association Forum

I was asked to look into what the J/105 fleet is doing. Some information:
1. No class rules prohibition.
2. On-line article about the change here for a J/105 sailboat , Thank you to X.X for bringing this to my attention. https://www.sailingscuttlebutt.com/2024/02/07/the-hard-charging-results ...

(Note: This reply provided by Dan Corcoran in order to gain consensus for Lithium Batteries does not imply endorsement by the Technical Committee)

October 2025 Annual Meeting Lithium Topic - When it’s time to replace your J/109 batteries, the only option currently allowed under class rules is ...

Lastly, you also want an alternator protection device wired into the engine compartment as well, especially if your battery has a battery management system (BMS) that can cut off the battery suddenly.

Here is more info:
Sterling Power Pro Protect 24v Alternator Protection Device Overview:

The Pro ...

Also from ChatGPT

ABYC standards do address fusing near alternators, though the requirements are a bit different from battery terminal fusing. Here’s the breakdown:

1️⃣ Fuse (or Circuit Protection) for Alternators

According to ABYC E-11 (DC Electrical Systems):

DC output from an alternator must ...

Courtesy of ChatGPT:

Here’s a clear summary of ABYC (American Boat & Yacht Council) requirements for fuses on marine batteries, focusing on what matters for safety with systems like lithium or lead-acid batteries:

1️⃣ Purpose of Fuses

Protect wires and equipment from overcurrent that can cause ...

Continuing on my reminder that drop-in batteries are not drop in, here is a good article about storage.

"LiFePO4 batteries have a special wrinkle, here is a good article explaining. As written by another commentor "This was an excellent, timely, well thought out article and, as the leaves north of ...

Never mind, new information, early 2026 will not have 12 volt product. First out is 24 volt batteries for heavy equipment.

LOL. Thank you for sharing yea, the symptoms didn't match up to blockage, but slippage? What was the cause of "sometimes" slipping, was it when the battery was partially discharged?

I have a fuse there also, which makes sense when the alternator is the source of current you want a fuse near by. Similiarly there are fuses on the cables for the shore chargers.

To be clear, none of these fuses need not be upgraded with the Odyseey or other TPPL lead acid batteries under the ABYC ...

Getting back to you on your fuse question. Bluesea systems are top rated products. Whenever I buy something else to save money, I find something strange about the alternate product, usually around how it mounts.

Option 1: T-Fuse, 20,000 AIC. Good up to 400 Ahr of TPPL or Lithium battery
https ...

Odyssey Extreme Batteries (these are TPPL lead acid batteries), they charge a bit faster giving you more usable capacity per lb.

ABYC, recognizing that TPPL batteries can more easily jump the fuse on a short to create a fire, now requires the same serious fuses as they do for lithium batteries = 5 ...

We’re likely to see new “drop-in” batteries on the market before January. Before anyone rushes to upgrade in Spring, maybe because your batteries didn't make the winter, here are a couple of points worth keeping in mind.

1. Class Rules

Our class rules need to be updated to keep pace with new ...

I suppose we are all hesitating to suggest one or more formally broken impeller vanes (blades) are causing an intermitten full blockage, got past the heat exchanger and accumulate somewhere, because the symptom would not be a full blockage. Here is an article, different boat, same engine about what ...

Yes, I would like to present this year. Here are my thoughts on timing and content:
- 2 min - Introduction. Who I am, benefits include lower boat ownership cost, faster charging / usable potential from same number of Ahr battery capacity, lower run time on diesel engines to recharge batteries ...

Exploring a Lithium Upgrade Path for J/109s – Who’s With Me?

I’m still very interested in developing an upgrade path to LiFePO₄ (lithium) batteries for J/109s. So far, I feel like I’m standing on an island, as owners don't speak up and swap out lead acid for class events.

Here’s why I’m writing ...