New batteries

[NBDensie]

When I went back to Densie after xmas I found the domestic batteries (4X110ah) were flat, and wouldnt recharge. Looks like I need new ones, the previous ones lasted 18months (about 5-6months solid usage). From previous threads and Tony Brooks website I understand that deep cycle 110ah would be appropriate. Most recharging will be done on the move using a modern 70amp alternator, no special controllers.

 

The only reasonable price batteries I could find on the net were NUMAX L110s. Are these OK? Assuming they will fit would there be any point going for 135ah's. Are there any others people would recommend? Is there somewhere good in the Braunston area to buy batteries?

 

Thanks for any advice.

 

Mike

Edited December 29, 2007 by NBDensie

[chris w]

When I went back to Densie after xmas I found the domestic batteries (4X110ah) were flat, and wouldnt recharge. Looks like I need new ones, the previous ones lasted 18months (about 5-6months solid usage). From previous threads and Tony Brooks website I understand that deep cycle 110ah would be appropriate. Most recharging will be done on the move using a modern 70amp alternator, no special controllers.

 

The only reasonable price batteries I could find on the net were NUMAX L110s. Are these OK? Assuming they will fit would there be any point going for 135ah's. Are there any others people would recommend? Is there somewhere good in the Braunston area to buy batteries?

 

Thanks for any advice.

 

Mike

 

Becuae of the non-linear nature of batteries (ie: they are not "really" 110AH or 135AH - this is just a single point of measurement on a curve) and the complex maths behind them, it is disproportionately better to buy 135AH versions rather than 110AH for example.

 

As an instance, 110AH batteries, in reality, have an actual AH value of 183AH and a 135AH battery has an actual AH value of 239AH.

 

So instead of the apparent 23% gain in AH value, the actual increase by using 135AH batteries is actually 31%. And the price difference between a 110AH and a 135AH is not as much as 31% so they are better value for money.

 

A modern 70AH alternator on the move will never get your batteries back up to 100%. Not unless you're cruising 20 hours per day! That is why your batteries have failed prematurely. You really do need to fit an alternator controller to achieve proper charging and proper charge cycles.

 

Also check that the new batteries are rated at the 20 hour rate ie: they state on the label 110AH or 135AH @ the 20 hour rate. There is some specsmanship sometimes played and a 90AH battery (at the 20 hour rate) can be truthfully stated to be a 110AH battery (although at the 10 hour rate). So do double check. Caveat Emptor.

 

Chris

Edited December 29, 2007 by chris w

[denboy]

18 months isnt a long time ,,i have 5 135 a bats that have been on here for going on 5 years and still going strong top em up every month in constant use, dont know anywere in braunstone but for gods sake stay away from chandelers shops rip off try finding a local baty supplier and haggle if your buying 4 get a good deal i paid £200 for mine and i baught 6 so shop around

 

 

 

 

think this is in your area

Midland Battery Specialist Ltd

20, Francis St, Northampton, Northamptonshire NN1 2NZ

Tel: 01604 630909

 

Classification: Battery Suppliers

Edited December 29, 2007 by denis boyle

[onthecut]

When I went back to Densie after xmas I found the domestic batteries (4X110ah) were flat, and wouldnt recharge. Looks like I need new ones, the previous ones lasted 18months (about 5-6months solid usage). From previous threads and Tony Brooks website I understand that deep cycle 110ah would be appropriate. Most recharging will be done on the move using a modern 70amp alternator, no special controllers.

 

The only reasonable price batteries I could find on the net were NUMAX L110s. Are these OK? Assuming they will fit would there be any point going for 135ah's. Are there any others people would recommend? Is there somewhere good in the Braunston area to buy batteries?

 

Thanks for any advice.

 

Mike

 

Hi Mike.

 

Must echo Chris' comment regarding an external controller ---- they really do help gee up the charging regime. Battery wise, if you have the time to watch and the space in your boat to fit them, keep an eye out on Ebay for genuine deep cycle units (ex hospital standby, that sort of thing) They will take up more space than the toy automotive type, but if you get lucky you will get unparalelled service from them. Often replaced in their original situation on a rolling maintenance plan, they will (typically) have had a cosseted existence and will give you years of further service.

 

Mike.

[Big Steve]

Becuae of the non-linear nature of batteries (ie: they are not "really" 110AH or 135AH - this is just a single point of measurement on a curve) and the complex maths behind them, it is disproportionately better to buy 135AH versions rather than 110AH for example.

 

As an instance, 110AH batteries, in reality, have an actual AH value of 183AH and a 135AH battery has an actual AH value of 239AH.

 

So instead of the apparent 23% gain in AH value, the actual increase by using 135AH batteries is actually 31%. And the price difference between a 110AH and a 135AH is not as much as 31% so they are better value for money.

 

A modern 70AH alternator on the move will never get your batteries back up to 100%. Not unless you're cruising 20 hours per day! That is why your batteries have failed prematurely. You really do need to fit an alternator controller to achieve proper charging and proper charge cycles.

 

Also check that the new batteries are rated at the 20 hour rate ie: they state on the label 110AH or 135AH @ the 20 hour rate. There is some specsmanship sometimes played and a 90AH battery (at the 20 hour rate) can be truthfully stated to be a 110AH battery (although at the 10 hour rate). So do double check. Caveat Emptor.

 

Chris

 

Chris,

 

If it's not too much trouble can you go into a bit more detail please. I'm confused re the Ah you quote of 183 and 239. Also doesn't a battery have a higher Ah rating at a lower discharge rate? eg You are stating that 90Ah at 20hours = 4.5 amps, 110Ah at 10 hours = 5.5 Amps for the same battery, I always thought it was the other way around.

 

Cheers

 

Steve

[NB Alnwick]

In view of the relative importance of battery quality - would it not be extremely helpful to have some recommendations from those who understand such matters?

 

Two years ago we paid out a small fortune for a set of 'Elecsol' deep cycle carbon fibre batteries but we are not yet convinced that they are better than the cheap and cheerful leisure batteries sold by Halfords. Having said that - we have no way of really knowing if we made a sound investment or just wasted our money.

 

Someone out there must know enough to be able to recommend the best buy in batteries . . .

Edited December 30, 2007 by NB Alnwick

[chris w]

Charles Sterling, the MD of Sterling Power, states in his catalogue that the best bet for wet-lead acid batteries is to buy the cheapest "leisure" batteries for domestic boat use. He reckons he can't find any difference between different priced batteries of this type. He further advises against both sealed and AGM type batteries for boats on the basis of very high cost and no improvement in either life or performance.

 

I beilieve I'm correct in asserting that Gibbo also said this some time back.

 

In response to Big Steve's question about the maths behind it, you can do no better than read Gibbo's pages on this on his website where he talks about the "Peukert Effect". His site goes into some very detailed and complex mathematics about battery capacity. (I know because I wrote the mathematical proofs on this topic for his site).

 

Start here at the base level and then get deeper and deeper into the maths if you so wish.

 

In answer to your specific query re 90AH and 110AH batteries, I rechecked my own maths and I did in fact make an error (apologies). The true figures are that a 90AH battery, quoted at the 20 hour rate, has exactly the same capacity as a 110AH battery quoted at the 48 hour rate. So do check the label on the batteries - not all batteries are quoted at the 20 hour rate - only most.

 

Although this possibly won't make sense until you have read Gibbo's pages, the maths is as follows:

 

The actual capacity of a 90AH battery quoted at the 20 hour rate is:

 

(90/20)^1.3 x 20 = 141AH

 

Similarly the actual capacity of a 110AH battery quoted at the 48 hour rate is:

 

(110/48)^1.3 x 48 = 141AH

 

Remember also that, in use, you should not run your batteries below 50% capacity (~12.2v off load) or you will severely shorten their life.

 

Chris

Edited December 31, 2007 by chris w

[David Schweizer]

For what it is worth I fitted two 6volt 230 amp ultra deep cycle batteries two ansd a half years ago. So far I have not had to top up the electrolyte and they hold their charge extreemly well. the last pair lasted eleven years.

 

This is where I got them from although they have gione up a buit in price recently.

 

http://www.batterymegastore.co.uk/cgi-bin/...ltra_Deep_Cycle

 

I also echo Chris W's advice about fitting an external alternater controller, I have a Sterling version and it does exactly what it says on the box.

Edited December 31, 2007 by David Schweizer

[chris w]

These do look like good batteries David. However, the manufacturers have errors IMHO in their maths regarding the amount of capacity needed. Firstly, they don't take the Peukert effect into account and, secondly, their maths assumes full discharge which will severly shorten the batteries' lives.

 

Ultra deep cycle batteries means that one can discharge them many more times than conventional "leisure" batteries. They presumably have much thicker lead plates, hence the additional cost. However, this still doesn't mean that they should be regularly discharged below about 50% otherwise their life too will be shortened.

 

Chris

[David Schweizer]

These do look like good batteries David. However, the manufacturers have errors IMHO in their maths regarding the amount of capacity needed. Firstly, they don't take the Peukert effect into account and, secondly, their maths assumes full discharge which will severly shorten the batteries' lives.

 

Ultra deep cycle batteries means that one can discharge them many more times than conventional "leisure" batteries. They presumably have much thicker lead plates, hence the additional cost. However, this still doesn't mean that they should be regularly discharged below about 50% otherwise their life too will be shortened.

 

Chris

Yes I understand that, but I have comparitively low demand on my boat and rarely use more than 60/70 amps between cruising, so it is unlikely to be a problem.

 

I have just checked and I actually have the US-125 (green) batteries which are 242 amps, and were supplied as alternatives to the advertised batteries because they were out of stock at the time. (same price but very heavy!!)

Edited December 31, 2007 by David Schweizer

[chris w]

Yes I understand that, but I have comparitively low demand on my boat and rarely use more than 60/70 amps between cruising, so it is unlikely to be a problem.

 

I have just checked and I actually have the US-125 (green) batteries which are 242 amps, and were supplied as alternatives to the advertised batteries because they were out of stock at the time. (same price but very heavy!!)

 

Heavy is good with batteries - it means the plates are really thick and they will have years and years of life if looked after.

 

Chris

[Ray]

Chris

 

At the risk of asking a question that's been asked more than once before, I've just read Gibbo's pages and don't really understand them - sorry Gibbo.

 

Our boat is just over a year old. It has a Beta 43 engine and two alternators, one for the starter and one for the leisure batteries - a bank of 5 110ah batteries. We also have a Mastervolt 2000 Combi unit and their remote (located) control panel, which we have yet to install. We're not far off fitting a bow thruster with its own two batteries, which we'll charge off the starter alternator.

 

Reading Gibbo's pages it looks as though we don't need to worry about an external alternater controller but his SmartGuage looks interesting. What benefits would his SmartGuage bring in our situation?

 

Gibbo doesn't seem to be posting at present, otherwise I'd direct this question at him.

[Chris Pink]

When I went back to Densie after xmas I found the domestic batteries (4X110ah) were flat, and wouldnt recharge. Looks like I need new ones, the previous ones lasted 18months (about 5-6months solid usage).

 

 

Just a small thought; I would be curious as to why they were so flat when you got back, sound like there may be a fault discharging the batteries and if they had been flattened all the way it would be difficult to get them to charge.

 

What did you use to attempt the recharge? Worth noting that a very flat battery won't excite some alternators, though i believe modern alternators are not so prone to this.

[chris w]

JWorth noting that a very flat battery won't excite some alternators, though i believe modern alternators are not so prone to this.

 

Actually even modern alternators need about 250mA to excite them initially. I suspect even a "flat" battery will deliver on this small amount. The usual reason for an alternator's not being excited is because the ignition lamp does not allow enough current to flow; maybe through the incorrect replacement lamp being fitted. The usual cure is to wire a 47 ohm 3W resistor in parallel with the lamp.

 

A friend of mine was told by his marina "engineer"(!) that he needed a new alternator on a second-hand boat he had just bought because the ignition light only went out when he revved up. I fitted a 47 ohm resistor in parallel with the lamp and now the ignition lamp and the alternator are both functioning perfectly.

 

With regard to Ray's question on alternator controller's, this is probably the one area where Gibbo and I disagree on their usefulness. I'm a big fan of them because I have one fitted (Sterling PDAR) with all the appropriate ammeters etc and I can SEE the difference in charge rate when I switch the alternator controller off and on. For me, it virtually doubles the charge rate once the battery voltage reaches the internal regulator voltage (from around 25A to around 50A). This is also the case, I know, for Blackrose who has two such units on his boat (one for domestics, one for start & BT batteries). Only yesterday, David Schweizer and Mike (onthecut) recommended them too.

 

It seems that the jury is out, until you try one, and then one becomes an instant convert. Seeing is believing. An alternator controller turns your alternator's charging regime from the equivalent of a Halfords-type car charger into a sophisticated multistage charger. You wouldn't use a car-type charger to charge your domestics when on shore-power, so why on earth would you want to do it when you're cruising?

 

With regard to the Smartgauge, IMHO it's a great piece of kit. It's not an alternative to an alternator controller but will give you an accurate reading of your battery state-of-charge (SOC). It does NOT measure Ampere-Hours used but gives the much more useful SOC measurement. ie: How much energy is left in the battery.

 

It is also very easy to fit as it only uses two wires (like a voltmeter). However, it is NOT just a voltmeter and measures the SOC in a very clever way, the principle of which I understand but won't reveal here. (That's up to Gibbo to do or not to do).

 

Smartgauge and an alternator controller together are the dog's whatsits IMHO.

 

Chris

Edited December 31, 2007 by chris w

[Speedwell]

The only reasonable price batteries I could find on the net were NUMAX L110s. Are these OK? Assuming they will fit would there be any point going for 135ah's. Are there any others people would recommend? Is there somewhere good in the Braunston area to buy batteries?

My local battery supplier seems to think quite highly of Numax. He said the ones I bought for my (diesel) cars were the same as used by Jaguar but relabeled. I had previously bought two 110Ah Numax leisure batteries when I changed from gas to an electric fridge. They are the cheaper, non-sealed type and no trouble after 2 seasons boating although the longest they have been in use without charging is only 3 days. They are left for long periods out of use as we are only holiday boaters.

Arthur

[chris w]

My local battery supplier seems to think quite highly of Numax. He said the ones I bought for my (diesel) cars were the same as used by Jaguar but relabeled. Arthur

 

They may indeed be great batteries and I'm not saying they're not but your battery supplier's recommendation was directed towards cars. In a car the ONLY job of the battery is to start the engine using maybe 1AH tops each time. Once started everything is run from the alternator. The battery plays no further role.

 

In a boat, with regard to the domestic batteries, it's a different story and so the two types of battery are not comparable and interchangeable.

 

Chris

[smileypete]

In view of the relative importance of battery quality - would it not be extremely helpful to have some recommendations from those who understand such matters?

 

Two years ago we paid out a small fortune for a set of 'Elecsol' deep cycle carbon fibre batteries but we are not yet convinced that they are better than the cheap and cheerful leisure batteries sold by Halfords. Having said that - we have no way of really knowing if we made a sound investment or just wasted our money.

 

Someone out there must know enough to be able to recommend the best buy in batteries . . .

If the batteries will get persistently undercharged then cheapo ones are probably best.

 

Unless there is the charging/monitoring kit and/or expertise to ensure they'll get fully charged, then there's not much point buying better batteries.

 

That said, ones that are too cheap might have quality control problems.

 

But have a look at:

 

http://www.canalworld.net/forums/index.php...st&p=132877

 

cheers,

Pete.

Edited December 31, 2007 by smileypete

[chris w]

If the batteries will get persistently undercharged then cheapo ones are probably best.

 

cheers,

Pete.

 

Why do you only recommend cheap ones if they are going to be persistently undercharged? If one has a proper charging regime why would you not also recommend cheap batteries? I don't understand the logic? What do you think the difference is between a £50 battery and an £80 battery of the same nominal capacity. Answer: £30, nothing else.

 

If one buys VERY expensive deep traction or ultra deep cycle batteries I would agree with you as otherwise you are wasting your money by abusing them.

 

Chris

Edited December 31, 2007 by chris w

[Keeping Up]

My local battery supplier seems to think quite highly of Numax. He said the ones I bought for my (diesel) cars were the same as used by Jaguar but relabeled. I had previously bought two 110Ah Numax leisure batteries when I changed from gas to an electric fridge. They are the cheaper, non-sealed type and no trouble after 2 seasons boating although the longest they have been in use without charging is only 3 days. They are left for long periods out of use as we are only holiday boaters.

Arthur

After many years of surprisingly successful use of Elecsol batteries, I changed them for Halfords leisure batteries (which were not cheap) because although they are made by Yuasa they were rumoured to be made on the old Lucas production line in Birmingham. They were satisfyingly heavy, but only lasted a few weeks and I got my money back.

 

So I asked Adverc, who made my alternator controller, on the basis that they should know what works best with their own controllers! They told me they sell two types from marine/leisure use, Numax and Varta. Their technical bod said that although the Varta are 50% more expensive than the Numax, in a typical narrowboat they generally last almost twice as long. I bought the Vartas; touch wood, after one summer, so far so good.

Edited December 31, 2007 by Keeping Up
Typos (again)

[Chris Pink]

After many years of surprisingly successful use of Elecsol batteries,

 

 

I also regret the demise of Elecsol, wonderful batteries, well priced, especially trade, almost always exceeded expectation, wonderful service and an understanding attitude to warranty.

 

I fitted loads of them and with very few exceptions they would make 4-5 years.

 

Wonder what happened to the plant?

[David]

Hi

Numax are made by Manchester Batteries, Manbat, and are sold by Midland Chandlers, Aquafax sometimes labeled for the customer with their badge etc.

I have used them for many years usually getting 4 to 5 years from them.

I just happened to be pricing them at my local Manbat 2 weeks before Christmas for a live aboard boater on our mooring, (I go there most weekends) and I priced them and others on the web for him. The 110 amp Leisure/marine was £68 plus vat at Manbat themselves, £62 plus vat trade to me, but Adverc BM in Wolverhampton still had them at coppers under £57 plus vat AND free delivery. The leisure one with a picture of a caravan on and in a green casing is the same battery as the black cased one with pictures of boats on, people are funny about having the right colour and picture so they do one for both main type of leisure battery customer.

 

I no longer have the link but put Manbat or Manchester batteries into your web browser and on the home page is a link to Adverc as a partener, or just browes for adverc they may still have them at this price.

david

edited to say

Should add i phoned Adverc to confirm the price and free delivery thinking it may have been trade and for a certain number, but was told it was correct and for any number from one up and I could buy there and then via card for delivery in 4/5 days.

david

Edited January 1, 2008 by David

[chris w]

Do the batteries from Adverc arrive filled as I thought that one couldn't send filled batteries by courier and that one had to get them filled at a local garage? I may be talking danglies on this one but I thought I read that somewhere.

 

Chris

[David Schweizer]

Do the batteries from Adverc arrive filled as I thought that one couldn't send filled batteries by courier and that one had to get them filled at a local garage? I may be talking danglies on this one but I thought I read that somewhere.

 

Chris

The Ultra Deep Cycle batteries I got were delivered filled and charged, so I guess it is allowed, although they may well have beenn sent in a specially adapted van with cages to prevent them moving.

[Keeping Up]

Do the batteries from Adverc arrive filled as I thought that one couldn't send filled batteries by courier and that one had to get them filled at a local garage? I may be talking danglies on this one but I thought I read that somewhere.

 

Chris

The batteries I received from Adverc were delivered by a specialist battery delivery company, ready filled and charged.

[Broughton 2]

Becuae of the non-linear nature of batteries (ie: they are not "really" 110AH or 135AH - this is just a single point of measurement on a curve) and the complex maths behind them, it is disproportionately better to buy 135AH versions rather than 110AH for example.

 

As an instance, 110AH batteries, in reality, have an actual AH value of 183AH and a 135AH battery has an actual AH value of 239AH.

 

So instead of the apparent 23% gain in AH value, the actual increase by using 135AH batteries is actually 31%. And the price difference between a 110AH and a 135AH is not as much as 31% so they are better value for money.

 

A modern 70AH alternator on the move will never get your batteries back up to 100%. Not unless you're cruising 20 hours per day! That is why your batteries have failed prematurely. You really do need to fit an alternator controller to achieve proper charging and proper charge cycles.

 

Also check that the new batteries are rated at the 20 hour rate ie: they state on the label 110AH or 135AH @ the 20 hour rate. There is some specsmanship sometimes played and a 90AH battery (at the 20 hour rate) can be truthfully stated to be a 110AH battery (although at the 10 hour rate). So do double check. Caveat Emptor.

 

Chris

 

Thanks Chris, I shall be buying batteries for my fit-out soon and appreciate comment that 135AH are best value. Sometime ago I was advised 6V batteries (coupled in series to give 12V) may also be better value than equivalent 12V. Care to comment on relative performance, value, problems, whatever?