Another Battery Question

[richardbrennan]

I am a bit reluctant to dip my toe in the water with another battery question at the moment, but would appreciate some advice.

It's clearly time to replace my Lifeline AGM batteries which are now more than ten years old. T-105s are not an option as they would require major surgery to the battery boxes, so I am looking at quality AGM batteries that are the same dimensions as the Lifelines.

I currently have two Lifeline 31Ts in the domestic bank and one 3100T as an engine start battery, the charging is handled by a voltage sensitive relay. The obvious replacements for the 31Ts would appear to be either the Trojan 31-AGM or the Rolls S12-128AGM. There would appear to be no obvious equivalent to the 3100T which has a CCA rating at 32 degrees F of 950. The Trojan 31 AGM is a little cheaper and has a CCA of 600 whereas the Rolls has a CCA of 760.

My questions are:

1) Does anyone have experience of these makes of batteries in terms of reliability etc.

2) If I fitted all three of the same type, would the CCA of 600 for the Trojan be sufficient for starting a Volvo D-130, or would I be safer going for the Rolls?

Many Thanks

Rick

 

[pvb]

For the domestic bank, the Rolls batteries are cheaper and have a theoretically better cycle life (1200 vs 1000 cycles to 50% DoD). I'd go for the Rolls batteries, you can get good quality AGMs for less, but with reduced expected cycle life. On balance, the Rolls should be cheaper in the long run.

The 3100T engine start battery has 950A cranking ability at 32F, however this isn't "CCA", it's MCA. CCA is measured at 0F. MCA is measured at 32F. The Rolls has an MCA of 910A, so it's almost identical to the 3100T, and will be more than enough to start a D1-30 engine. The Trojan has an MCA of 720A, so a bit less than the Rolls, but would still happily start your engine.

 

[PaulRainbow]

Mentioned this a couple of times recently, https://www.batterymegastore.co.uk/...batteries/boat-batteries/hankook-sa57020.html

I fiited a few recently, work really well and a 5 yr warranty.

 

[richardbrennan]

pvb

Many thanks for a most useful post. I think, all other things being equal, I would go for the Rolls based on your advice. However, I am struggling to find them at a cheaper price than the Trojans. Tanya batteries are the cheapest I can find for both, but the Rolls are £20 more expensive and for some reason have a delivery charge of £37.99 compared to £10.99 for the Trojans, which I find difficult to understand given that they are virtually the same size and weight; interestingly the delivery charge for the Lifelines is also £10.99! This makes Barden the cheapest overall as, assuming their price includes VAT, they are £10 more expensive than Tanya at £279, but this includes free delivery. If I am looking in the wrong place, please let me know.

I am planning to go down to my boat tomorrow and will measure up as the S12-128AGM is slightly larger than the Lifelines, if the're too big I'll have to go for the S12-116AGMs

PaulRainbow

Thanks for the suggestion, but I want to stick to at least 105 amp/hours.

 

[PaulRainbow]

PaulRainbow

Thanks for the suggestion, but I want to stick to at least 105 amp/hours.

Your choice of course Richard, but cranking amps are the important figure for engine starting, not a/h. The Hankook battery is more than capable of starting a D1-30, i've been fitting them to much bigger 4 cylinder engines. I'd also question the logic of fitting a deep cycle battery for engine starting.

 

[pvb]

pvb

Many thanks for a most useful post. I think, all other things being equal, I would go for the Rolls based on your advice. However, I am struggling to find them at a cheaper price than the Trojans. Tanya batteries are the cheapest I can find for both, but the Rolls are £20 more expensive and for some reason have a delivery charge of £37.99 compared to £10.99 for the Trojans, which I find difficult to understand given that they are virtually the same size and weight; interestingly the delivery charge for the Lifelines is also £10.99! This makes Barden the cheapest overall as, assuming their price includes VAT, they are £10 more expensive than Tanya at £279, but this includes free delivery. If I am looking in the wrong place, please let me know.

I meant that the Rolls were cheaper than the Lifeline 31T, and 1200 vs 1000 cycles. The Trojans are about £20 cheaper.

As PaulRainbow has said, you don't need a deep-cycle battery for your engine start, any reasonable AGM battery would do. I say AGM as you may need to charge all the batteries at the same voltage. One advantage of getting 3 identical batteries is that you could always swap them around in the future, or indeed put the 3 together as a bigger house bank (one of the most cost-effective improvements you can make) and get a new starter battery.

 

[richardbrennan]

I am a bit concerned now following Paul's comment. Whilst I realise a deep cycle battery is not necessary or perhaps ideal for engine starting, is there any reason I should not use one assuming the CCA are sufficient, will I do the battery any damage?

 

[pvb]

I am a bit concerned now following Paul's comment. Whilst I realise a deep cycle battery is not necessary or perhaps ideal for engine starting, is there any reason I should not use one assuming the CCA are sufficient, will I do the battery any damage?

You won't do it any damage, if the CCA is sufficient, but you just don't need to pay the extra cost of a deep cycle battery if it's only for engine starting. Unless, as I suggested, you might want to use it for something else in the future.

 

[PaulRainbow]

I am a bit concerned now following Paul's comment. Whilst I realise a deep cycle battery is not necessary or perhaps ideal for engine starting, is there any reason I should not use one assuming the CCA are sufficient, will I do the battery any damage?

I dare say that there will be those who say they have used deep cycle batteries for years with no ill effect and those that say the opposite. I re-wired a 60ft boat earlier this year and the owner had previously fitted Rolls deep cyle for engine starting, he reported that they did not last long at all.

I think key points are, there is absolutely no benefit to using them, they are certainly not best suited for engine starting and will cost two to three times the price of decent "normal" agm batteries.

 

[richardbrennan]

Hi Paul

In view of your comments, I might have a re-think. If I fit the Rolls or Trojans for the domestic bank, am I likely to have a charging regime issue if I fit a normal AGM, such as the one you suggest, as a starter battery? Ideally I would like a larger size for the starter, not for the amp hours, but just to fit more securely in the current battery box.

 

[PaulRainbow]

Hi Paul

In view of your comments, I might have a re-think. If I fit the Rolls or Trojans for the domestic bank, am I likely to have a charging regime issue if I fit a normal AGM, such as the one you suggest, as a starter battery? Ideally I would like a larger size for the starter, not for the amp hours, but just to fit more securely in the current battery box.

Set the charger for the deep cycle batteries Richard and the normal AGM will be fine.

Does this fit your box better https://www.batterymegastore.co.uk/hankook-sa59520.html

No connection with BMS or Hankook, other than having fitted many, many of their batteries and never had an issue <touch wood>

 

[richardbrennan]

Hi Paul

Hi Paul
I'll measure up tomorrow, but I think this one might be a bit big; I see there's one in between that might be my best option. I am wondering if I actually need to replace the starter battery at this time. It's showing no signs of deterioration and starts the engine almost instantly. Would this be a problem if I replace the domestic bank? As I said earlier, they are seperated with a VSR, the function of which, I must admit I do not fully understand, not helped by the wiring diagram that I have in the owner's manual shows a splitting diode.

Many Thanks

Rick

 

[pvb]

Set the charger for the deep cycle batteries Richard and the normal AGM will be fine.

The deep cycle batteries he's considering are AGMs, so charging can't be an issue.

 

[PaulRainbow]

The deep cycle batteries he's considering are AGMs, so charging can't be an issue.

I know, that's why i said they'd be fine If he fits the Rolls batteries, be worth double checking the charger settings/battery requirements, i seem to think Rolls specify a little higher than Lifeline ?

 

[PaulRainbow]

Hi Paul

Hi Paul
I'll measure up tomorrow, but I think this one might be a bit big; I see there's one in between that might be my best option. I am wondering if I actually need to replace the starter battery at this time. It's showing no signs of deterioration and starts the engine almost instantly. Would this be a problem if I replace the domestic bank? As I said earlier, they are seperated with a VSR, the function of which, I must admit I do not fully understand, not helped by the wiring diagram that I have in the owner's manual shows a splitting diode.

Many Thanks

Rick

If it's working OK, leave it Richard. Replace as and when required with an AGM starter battery.

 

[richardbrennan]

Hi Guys

Again, many thanks for your advice.

Having been down to the boat today, I have checked out the settings on my charger. Currently it's set on a charge voltage of 14.2 and a float voltage of 13.3, although having checked with my voltmeter it seems to be putting out about 14.15 and 13.2 at the actual battery terminals. This is OK for the Lifelines which quote a charge range of 14.2 to 14.4 and a float range of 13.2 to 13.3. I think having looked at the options available from the charger, the Rolls batteries rule themselves, out so I am looking at the Trojans which quote a charge rate of 14.1 to 14.7 and a float of 13.5. Obviously the float I currently have is a little lower and I do have an option to change the range to 14.4/13.9. This is a bit high on float for both the Trojans and the Lifelines, which setting would you recommend, is it better to be a bt higher or a bit lower on the float voltage?

 

[PaulRainbow]

Hi Guys

Again, many thanks for your advice.

Having been down to the boat today, I have checked out the settings on my charger. Currently it's set on a charge voltage of 14.2 and a float voltage of 13.3, although having checked with my voltmeter it seems to be putting out about 14.15 and 13.2 at the actual battery terminals. This is OK for the Lifelines which quote a charge range of 14.2 to 14.4 and a float range of 13.2 to 13.3. I think having looked at the options available from the charger, the Rolls batteries rule themselves, out so I am looking at the Trojans which quote a charge rate of 14.1 to 14.7 and a float of 13.5. Obviously the float I currently have is a little lower and I do have an option to change the range to 14.4/13.9. This is a bit high on float for both the Trojans and the Lifelines, which setting would you recommend, is it better to be a bt higher or a bit lower on the float voltage?

I'd leave it where it is with the Trojans Richard.

 

[pvb]

I think having looked at the options available from the charger, the Rolls batteries rule themselves, out so I am looking at the Trojans which quote a charge rate of 14.1 to 14.7 and a float of 13.5. Obviously the float I currently have is a little lower and I do have an option to change the range to 14.4/13.9. This is a bit high on float for both the Trojans and the Lifelines, which setting would you recommend, is it better to be a bt higher or a bit lower on the float voltage?

Why do the Rolls rule themselves out? If you look at the Rolls Battery Manual (http://rollsbattery.com/wp-content/uploads/2018/01/Rolls_Battery_Manual.pdf) the recommended charge voltages at 20C are 14.84 and 13.94, so the alternative setting on your charger would be fine.

 

[richardbrennan]

Hi pvb

I assumed that being nearly half a vote down on charge would be a bit much and a float of 13.9 for the remaining Lifeline is a bit high; am I wrong? Is there any particular reason behind your preference for the Rolls?

 

[PaulRainbow]

Hi pvb

I assumed that being nearly half a vote down on charge would be a bit much and a float of 13.9 for the remaining Lifeline is a bit high; am I wrong? Is there any particular reason behind your preference for the Rolls?

My reasoning is the same as yours Richard.