New Bow Thruster Battery Needed - Lucas Premium 624

[Richard10002]

Hi,

Existing Bow Thruster battery is a Lucas Premium 624 (200Ah), and it is at the end of its' useful life.

Having looked at the Lucas pdf, it seems that the battery is a 12V Maintenance free used in a variety of trucks, but it is not a leisure battery with deep cycling properties

http://www.lucas-electrical.co.uk/lucas/catalogues/XCB901LBatteriesCatalogue.pdf

It has a DIN 705-16

I'd like to replace it with a battery more suited to deep cycling, but would ideally want one with the same size and shape, (so I dont have to re-jig the support and securing arrangement), and perhaps with more capacity.

Any ideas how to source one.

Cheers

Richard

 

[cliff]

A 625-H might just fit although a few mm longer than the original. - worth looking at it?
--------------------

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[Pye_End]

How much current does a bow thruster draw, and how big is the discharge?

Presume a leisure battery will give you enough welly?

If you do not dicharge the battery very far, then a traction battery may be better.

Don't have any knowledge of bow thrusters at all, but assume you have been through the numbers?

 

[Talbot]

If you replace a bow thruster battery with a deep cycle type you will be making a bad mistake. The thruster requires a high CCA rating (cold cranking amps) as its performance is much more akin to an engine start than to a slow drain like a domestic system. You need to find out the CCA requirement for that battery and then match the battery to that. An engine start battery has the strength to manage the high currrent drain, whereas this high current load would destroy a deep cycle one.

There is one (more expensive) alternative, which is to fit a hybrid battery such as the Elecsol which has the strength to be used for high CCA, and also has deep cycle characteristics.

A lot of manufacturers use the optima battery (has similar characteriostics to the Elecsol)

 

[andy_wilson]

Redundancy.

I would endeavour to use the same battery for the bow thruster as either the engine start battery, or preferably, those used in the domestic banks. That way you have one less 'alternative' to carry.

I can't think of a good reason why it NEEDS to be deep cycle for a bow thruster. By the nature of the application, it will be used in bursts, almost certainly whilst the engine is running.

FWIW - all my batteries are the same. 130Ah truck batteries suitable for tail-lift vehicles, designed to start a huge engine after an hours heavy discharge through a hydraulic pump.

 

[hairbox]

Have you looked at the Redflash range light high CCA, GEL so you can mount them any way you want?

 

[Sailfree]

When I looked into this I was advised that due to the pounding near the bow you should get a spiral wound battery. As per the picture in someone elses post.

 

[howardclark]

Agree completely that an engine type battery is more suitable.
For my 80kg Vetus thruster I use an (80 amp I think) Optima. Fitted 5 years ago, has performed very well so far.

 

[patricmaude]

I would replace with a similar battery. As previous posts have mentioned, your bow thruster uses high amperage for a relatively short period. The CCA is the critical criterion. If you have wet cell batteries in your domestic and engine start banks, it would be a mistake to fit a gel or AGM battery as they have different charging characteristics. It is always a mistake to mix battery types unless they have different chargers, matched to their required charge characteristics

 

[dulcibella]

A no-maintenance battery has looked after my bowthruster very well. After all, you are only going to use it for a few seconds to turn the bow in a tight corner, so deep discharge isn't an issue. I'm not convinced by Sailfree's "pounding in the bow" argument, but perhaps that's because this just doesn't happen in a long keeler.

 

[Richard10002]

Thanks for all the replies. What I didnt say was that it also runs the 240V invertor system, (retro fitted), which is where I get the deep cycling thought from.

From the Lucas pdf, it looks like the 624 is specified for a number of trucks, so maybe it's the one to use.

 

[Sailfree]

Obviously the type of boat influences the amount of pounding but my research turned up that its recommended as best by the bow thruster manufacturers/fitters.

In my case I was checking that they were not cutting corners and they were not!

 

[Steve C Cronin]

Gel batteries are not the ideal choice for bow thrusters or windlasses. Their characteristics suit them better to house battery usage where the need is for a prolonged drain down to relatively low voltages, deep cycling, in other words. They also require careful and sophisticated charging arrangements. Flooded or conventional liquid lead acid are much more suitable as they can deliver the type of service required, i.e. short bursts at very high amperage levels. There is a boat here having trouble with his bow thruster power arrangements at the moment. The battery only shows 12.17 volts and has been on charge since last evening. A fully charged Gel battery should show 12.7 volts.

My feeling is that gel batteries are for those who like to buy what they conceive as the best and like showing off "Conspicuous Affluence" to their friends, like hackers buying "Ping" golf clubs. Mr Charles Sterling is also much in favour of flooded open batteries for most marine applications, incidentally.

 

[Richard10002]

Thanks for the input Steve..... I'm now well armed to finalise my decision, after 8 years of procrastination

 

[Plevier]

Gel batteries are not the ideal choice for bow thrusters or windlasses. Their characteristics suit them better to house battery usage where the need is for a prolonged drain down to relatively low voltages, deep cycling, in other words. They also require careful and sophisticated charging arrangements. Flooded or conventional liquid lead acid are much more suitable as they can deliver the type of service required, i.e. short bursts at very high amperage levels.

I agree with these comments taken exactly but please don't equate gel with AGM (as Sterling does).
The RedFlash referred to in an earlier post as gel is actually AGM.
AGM batteries are extremely good for high rate discharge and will also recharge quickly (though with most of them you have to be careful about voltage). Some of them have a decent cycle life, but that isn't an automatic result of being AGM, many AGMs don't have a good cycle life (just like most flooded batteries).
Gel batteries are not good for high rate discharge and can't be recharged quickly. TBH I don't think gel batteries have any place on boats.