Talador this is from the group I'm speaking of and the gentleman who wrote this particular msg is just one of several professionals who actually make their living converting boats to electric. While you could easily spend several $100 k if you want you are way off on conversion costs. And if your propulsion system is electric your diesel backup generator can be significantly cheaper and smaller than a drive engine.
From: "James Lambden james@electroprop.com [electricboats]" <electricboats@yahoogroups.com>
Blue Plus batteries can be charged at a lower rate of charge (less amps), and at any voltage between 14.3 and 14.7 volts. This allows you to make a bigger battery bank. The limiting factor of a large battery bank is the shore power circuit.
A 30 amp shorepower circuit is derated to 24 amps when used for more than 4 hours under NEC. Since charging a big battery bank takes more than 4 hours, we need to observe this recommendation. Its for good reason too. I have repaired lots of shore power inlets that have failed, many burn and smoke. As a marine electrician, this is a fairly common service call, and most often on the liveaboards as they are often using 2 heaters at 15 amps a piece total 30 amps for extended periods of time.
Not sure about the Oasis, but I thought they only came in a 116 amp hour battery which is too small for electric cruising boats though could be used on racing boats to get out to the start line.
Using 8 of these 116 amp hour batteries in a series parallel array making 48 volts adds much wiring and complication and expense to the battery system. If in parallel, safety is compromised if the batteries have the potential to fail with a shorted cell as regular AGM technology does - (Note - check on this before paralleling the Oasis battery )
I've have talked extensively to Northstar and their battery is really top of the line, and significantly better than any standard AGM battery, and can be paralleled completely safely, and have inherently safe technology. These batteries are very forgiving batteries.
I think it worthy to mention that every boat is different. If you daysail your boat and recharge your batteries each time upon return or have solar on board, the PSOC is not that important. If your duty cycle requires PSOC, then by all means make this the most important feature to shop by.
What I really like about the Northstar is the high degree of safety that comes with pure lead technology and the low charging current requirement.
The 216 amp hour Odyssey requires a charge rate of 80 amps to get the rated cycle life. The 210 amp hour Blue Plus can function of 25 amps of charging without derating cycle life. Safety and Low Charge Current Requirement are in many cases more important requirements than PSOC capability - though that is definitely an added bonus.
James Lambden
The Electric Propeller Company
625C East Haley Street,
Santa Barbara, CA
93103
805 455 8444
james@electroprop.com
www.electroprop.com
You are dead on with this Mike. So I suppose the lesson learned (and
hopefully passed on to future researchers), is this:
Northstar's red series is a no go for Electric propulsion battery banks.
Northstar's Blues are- Northstar confirmed the 210 FT is the same as the
SMS AGM 480 (Note: 480 is part of model name, and this time NOT amp hours)
mike@electricyachtssocal.com [electricboats]:
> The red batteries are designed internally with a different cell grid than the traditional blue batteries. Both are TPPL. The Red are designed for support telecom industry and sit for extended periods of time with a float charge in which they are called upon very rarely to support remote communications and backup. The Blue are designed to be discharged on a regular basis with extended cycling capability.
> The batteries do have carbon technology to support the batteries ability to stay in a partial state of charge and not be damaged. The plates are TPPL without Calcium that also support the issues of reduced sulfation.
> Mike
> Electric Yachts of Southern California/Pacific
>