Deep cycle domestic batteries-which ones should we buy?

Tidewaiter2

Tidewaiter2

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Our domestic deep cycle batteries are not holding charge, and it looks like their time may be up.
Size is important:D and our current 3+yo ones were bought hastily on a cruise when the earlier ones died.

Now we know the end is nigh, what are the Forum experiences of
Varta Professional LFs 105 versus Trojan 27 TMH

Current batteries are 110ah, 340lx170wx230h

A Varta 105ah is 330x175x240, wt26.9kg for £117.23

A Trojan 115ah is 324x171x248, wt 28kg for £200.56

Battery Box floor plate surgery is therefore fairly minimal for both. Height is ok for both.
Our Sailing is mostly coastal/X Channel/N Sea. Some anchoring, mostly harbours or marinas these days.

Are 2xTrojan really worth nearly another £200 for 20ah, and 1.1kg of lead plate?

All thoughts welcome
 
I'd get 2 Trojan T105 which will give you 225Ah at 12v. About £120 each delivered from Tanya or Battery Megastore. Not sure of sizes, but I would alter the storage area to make them fit.
 
Tidewaiter2 said:
Our domestic deep cycle batteries are not holding charge, and it looks like their time may be up.
Size is important:D and our current 3+yo ones were bought hastily on a cruise when the earlier ones died.

Now we know the end is nigh, what are the Forum experiences of
Varta Professional LFs 105 versus Trojan 27 TMH

Current batteries are 110ah, 340lx170wx230h

A Varta 105ah is 330x175x240, wt26.9kg for £117.23

A Trojan 115ah is 324x171x248, wt 28kg for £200.56

Battery Box floor plate surgery is therefore fairly minimal for both. Height is ok for both.
Our Sailing is mostly coastal/X Channel/N Sea. Some anchoring, mostly harbours or marinas these days.

Are 2xTrojan really worth nearly another £200 for 20ah, and 1.1kg of lead plate?

All thoughts welcome
Click to expand...

I bought Numax 110 amphr leisure batteries from the local farm place, used for electric fences.
Had them 5 yrs, still going strong. About £75 each, I did a farmers deal on them! how much for 3?
Stu
 
Trojan do a 130AH battery which is the same size as the lower AH ones so fits in the same box. It also has studs rather than posts which I find better. Battery Megastore do them. Dont have the code here but its easily found on their website.
 
Richard10002 said:
I'd get 2 Trojan T105 which will give you 225Ah at 12v. About £120 each delivered from Tanya or Battery Megastore. Not sure of sizes, but I would alter the storage area to make them fit.
Click to expand...
+1 For box mod & T105s, that's route I went down.

N.B. T105s have 2x expected life of Trojan 12V model you mention. I had Trojan tech. guys email graphs for both and T105 was expected to give 2x cycles. Both Trojan products so no obvious reason for them to fudge the results
 
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Those Varta are dual purpose batteries according to Varta. If you are looking for house bank batteries you would be better off with the Varta Hobby series which will discharge to 60% without harm. Notice the extra lead in them compared to the LF 105 (28kgs v 23kgs). Ohand they will still start our Volvo 2003 if we need too.

http://www.tayna.co.uk/813010-Varta-Hobby-Leisure-Battery-A28-P3641.html
 
Pete7 said:
Those Varta are dual purpose batteries according to Varta. If you are looking for house bank batteries you would be better off with the Varta Hobby series which will discharge to 60% without harm. Notice the extra lead in them compared to the LF 105 (28kgs v 23kgs). Ohand they will still start our Volvo 2003 if we need too.

http://www.tayna.co.uk/813010-Varta-Hobby-Leisure-Battery-A28-P3641.html
Click to expand...

When I was looking for batteries last year, someone knowledgeable on a motor home forum suggested the Varta 105Ah could be discharged further than the 110Ah, thus we're actually a better buy. I bought 3 x 110Ah Hobby Leisure and,,after a year, they're knackered - probably due to me but nothing special about them.
 
Richard that is true, just a bit more lead than el cheapo batteries whih makes the difference. I thought yours failed due to under charging though.

Pete
 
Pete7 said:
Richard that is true, just a bit more lead than el cheapo batteries whih makes the difference. I thought yours failed due to under charging though.

Pete
Click to expand...

That's the concensus, which is why I said probably due to me. I just didn't find the Varta batteries any better than the cheapo batteries the previous year, and had heard that the 105Ah Vartas are probably better than the 110Ah - more expensive for a reason?
 
Tidewaiter2 said:
...Our Sailing is mostly coastal/X Channel/N Sea. Some anchoring, mostly harbours or marinas these days...
Click to expand...

My take is that your choice of battery will depend a lot on your charging regime and usage. A battery life is related to the depth of discharge, how often its cycled and how fully they are recharged after use (oh and the battery design). An example - the house batteries I have should do 1400 charge cycles if only discharged by 30%; take that down to 50% and I can expect 650 cycles.

If you regularly plug into shore power and have a good, 3 or 4 stage, mains charger that fully charges the batteries and you dont run the batteries way down it may not matter which you choose. All things being equal you'll get a longer life out of the battery with more lead in.
 
On my previous boat I had some Varta Batteries. To me this Varta brand is mostly about perception. Maybe in former days they were superior but for me it's just a inflated brand name.

To your question. You should consider the place where the batteries are located. The drawback on the Trojan batteries (whilst being good batteries) is they are open (as in not sealed). So you need good ventilation and good access to top them up regularly. If you have limited access and if they are located in below a bunk, you may want to consider sealed batteries. AGM batteries may be a valid choice in such a case.
I've got Mastervolt AGM. The added advantage is they accept charge at a relative high current, so they charge a bit faster if your charger can accommodate.
I looked into the gel-battery story as well, but I decided not to have those as they are quite expensive. The AGM models are a nice compromise.

Arno
 
aluijten said:
On my previous boat I had some Varta Batteries. To me this Varta brand is mostly about perception. Maybe in former days they were superior but for me it's just a inflated brand name.

To your question. You should consider the place where the batteries are located. The drawback on the Trojan batteries (whilst being good batteries) is they are open (as in not sealed). So you need good ventilation and good access to top them up regularly. If you have limited access and if they are located in below a bunk, you may want to consider sealed batteries. AGM batteries may be a valid choice in such a case.
I've got Mastervolt AGM. The added advantage is they accept charge at a relative high current, so they charge a bit faster if your charger can accommodate.
I looked into the gel-battery story as well, but I decided not to have those as they are quite expensive. The AGM models are a nice compromise.

Arno
Click to expand...

I'd tend to agree with the opinion re Varta.
And, in reply to the OP, not all Trojan batteries are equal. Their 6v (T105 I think) are still considered by many the yardstick for battery longevity.
However, unless you have to rebuild the boat to fit replacement batteries, none of the high-end batteries seem to give as low a TCO as the cheapest, heaviest, locally made, open batteries. I only need to top mine up monthly - so no big deal.
For one particular battery box size, I can only get sealed batteries. Though they experience half the number of cycles of the other battery, their lives are only 5-7 years whereas the open battery gives 7 - 10 years.
No doubt Troubadour will be along shortly to correct my errors. ;-)
 
I would have gone for the Trojan batteries if they weren't so tall that they won't fit into the space available. In the end I went for these: http://www.advancedbatterysupplies.co.uk/abs100ahagmbattery - they weigh 31kg which is considerably heavier than most batteries of that capacity, so lb for £ at least I feel I've done OK!

There seems to be contradictory advice on the max charging voltage for AGM batteries, with one website stating that you will destroy them if you use more than 14.2V, whilst others suggest that they can be charged at a slightly higher voltage than a normal lead acid battery. Confusion reigns.
 
I believe that only Banner, Trojan, Varta and Exide make 'wet' deep cycle leisure batteries, the rest are standard batteries marked up as leisure. The best indication seems to be if they conform to EN 50342. I purchased a couple of Banner energy Bull yesterday, 135ah for £250 the pair. http://www.ebay.co.uk/itm/111273008022?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649

Banner or Trojan are your best bet.

http://www.ebay.co.uk/itm/27TMH-Trojan-Battery-Deep-Cycle-/281127436921?pt=UK_CarsParts_Vehicles_BoatEquipment_Accessories_SM&hash=item4174804279

It's worth reading this caravan club thread on the results of their battery test.

http://www.caravanclub.co.uk/community/discussions/technical-and-advice/caravans/Leisure-Batteries---shocking-truth/rt/622019/
 
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RobbieW said:
My take is that your choice of battery will depend a lot on your charging regime and usage. A battery life is related to the depth of discharge, how often its cycled and how fully they are recharged after use (oh and the battery design). An example - the house batteries I have should do 1400 charge cycles if only discharged by 30%; take that down to 50% and I can expect 650 cycles.

If you regularly plug into shore power and have a good, 3 or 4 stage, mains charger that fully charges the batteries and you dont run the batteries way down it may not matter which you choose. All things being equal you'll get a longer life out of the battery with more lead in.
Click to expand...

+1.

The OP doesn't give figures for Ah use between charges or the recharge regime. Both need balancing with the battery bank capacity.

If you have a smart charger, then changing battery type (EG wet to AGM) may mean you need to change the starter battery to the same type so that the charging algorithm is correct for both; worth bearing in mind.

To drift a little....

It's also interesting to look at how battery life changes with discharge depth and the lifetime cost of Ah. Robbie's cycle figures are interesting to compare with T105s.

For Robbie's new batteries (per 100Ah capacity);
- The lifetime capacity at 30% discharge/charge is 1400 X 30Ah = 42000Ah.
- For 50% discharge the lifetime capacity drops to 650 * 50Ah = 32500Ah.
- That's a difference of (42000 - 32500) / 42000 = 0.23 or 23%.

For the T105s (per 100Ah capacity);
- The lifetime capacity at 30% discharge/charge is 2780 X 30Ah = 83400Ah.
- For 50% discharge the lifetime capacity drops to 1650 * 50Ah = 82500Ah.
- That's a difference of (83400 - 82500) / 83400 = 0.01 or 1%.

There is a perception that battery life is increased if the discharge is limited to 50%. But that assumes it is the number of discharge/charge cycles which is important and takes no account of the energy used or replaced.

With the calculations above we can get a cost for energy over the battery lifetime.

T105s from Tayna are £110, that's £220 to make a 12V bank (carriage excluded).
T105s nominal capacity is 225Ah.
Depth of discharge Lifetime cost/Ah
20% 0.122p
30% 0.117p
40% 0.119p
50% 0.119p
60% 0.116p
70% 0.115p
80% 0.118p
90% 0.122p
100% 0.130p

The calculations make it possible to compare the cost of buying batteries that allow a deeper discharge with those that would need a greater capacity to provide the energy you need with lower depth of discharge. EG To get 180Ah from T105s requires them to be discharged to 80%. An alternative battery that would be better limited to 50% discharge would need to be 360Ah to get the same 180Ah.

All of the above assumes the discharge rate is constant and at the nominal (20 hour) rate.
 
As JohnGC's sums show, adding more battery capacity enables less discharge depths for the same consumption. My advice is to make some more space for extra batteries. 225 Ah at 12V is on the low side for liveaboard consumption. I have 440 Ah and still would like more. However, my dear old wet cell "marine" batteries have hung on 11 years now, so maybe I have enough. If your starter battery is of the same volume as your domestic batteries, it could be added into the bank and a small AGM or a TPPL battery tucked away somewhere near the starter motor. I have an Odyssey battery for this purpose.
http://www.odysseybatteries.com/
Of course the charging system needs to accept the different battery types.
 
So many variables that it does become confusing. There are space limitations, ventilation, personal factors (e.g. can't be bothered with maint.), usage, charging regime and so on.

I found a spreadsheet online which proved that T105s weren't the best bet for my boat. However, all the hidden data was old and US based. I plugged in 2012 UK price data for several makes and T105s jumped to the top of the list again. They were a bit of a pain to fit into the space but were the best bet for me. Price was not a lot more than many 12V leisure and less than Trojan 12V range. Trojan were able to supply specific data for lifecycle vs. discharge depth and T105s beat Trojan 12V by a factor of 2. That clinched it for me. I couldn't bring myself to buy a more expensive version with 50% expected lifetime. The financial risk was a lot lower than AGMs I considered and not a lot higher than many leisure batteries.

Worked for me but def. won't suit everyone.

Remember, capacity will vary with age, temperature and current draw so 225Ah from a T105 is just a starting point. Trojan claim 250Ah if current draw is only 2.5A for 100 hours at 25C. Conversely, a weedy battery might be discharged at more than the 20 hour rate and not provide the capacity quoted.
 
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