6 T-105 OR 4 TROJAN J305E-AC?

[Sailorman Ed]

I am trying to decide how much battery to add. Based on 530 watts of solar, can can easily fit 4 of the J305E-AC ( 305 AHr) or with difficulty, 6 of the T-105. Previously, we had 270 watts and 359 AHr of gel cells so even 2 of the T-105s are a 25% improvement. We expect to use about 20% more electricity on the new boat. Is 530 watts too much for 450 AHr? The J305 are a 20% premium per annualized AHr/life cycle.

Also looked at the Duracell EGC2 (230 AHr) - they are 20% less than the T-105 and slight shorter ( = less space under the plates?) Gets confusing quickly.

[btrayfors]

Originally Posted by Sailorman Ed

I am trying to decide how much battery to add. Based on 530 watts of solar, can can easily fit 4 of the J305E-AC ( 305 AHr) or with difficulty, 6 of the T-105. Previously, we had 270 watts and 359 AHr of gel cells so even 2 of the T-105s are a 25% improvement. We expect to use about 20% more electricity on the new boat. Is 530 watts too much for 450 AHr? The J305 are a 20% premium per annualized AHr/life cycle.

Also looked at the Duracell EGC2 (230 AHr) - they are 20% less than the T-105 and slight shorter ( = less space under the plates?) Gets confusing quickly.

Six T-105s will give you 675AH capacity. I'd go with that.

Bill

[DotDun]

Originally Posted by Sailorman Ed

I am trying to decide how much battery to add. Based on 530 watts of solar, can can easily fit 4 of the J305E-AC ( 305 AHr) or with difficulty, 6 of the T-105. Previously, we had 270 watts and 359 AHr of gel cells so even 2 of the T-105s are a 25% improvement. We expect to use about 20% more electricity on the new boat. Is 530 watts too much for 450 AHr? The J305 are a 20% premium per annualized AHr/life cycle.

Also looked at the Duracell EGC2 (230 AHr) - they are 20% less than the T-105 and slight shorter ( = less space under the plates?) Gets confusing quickly.

You do know that batteries you mention are 6v?

(2) T-105's are only 225ah @ 12v.

[laika]

I recently ditched 3 group31 AGMs (270AH) for 2 Trojan J185Ps at (410AH). The high profile 185s fit well in my space and actually take up a significantly smaller footprint than the 31s used to.

If you have the height, L16s are also worth a look.

If budget is not overriding priority, why not take some measurements and go with whatever will fit the best for you?

[Sailorman Ed]

Six T-105s will give you 675AH capacity

Bill - well 4 of the J305E will give almost as much and fit better but I have not seen anyone using these for some reason

You do know that batteries you mention are 6v?

(2) T-105's are only 225ah @ 12v.

Yes, quite aware of voltage and 4 of them will provide 450 AH I was wondering if 450 is enough and a good match for the solar panel wattage

I recently ditched 3 group31 AGMs (270AH) for 2 Trojan J185Ps at (410AH).

I will take a look at the J185. The L16s look great but are a bit pricey
I can squeeze in 6 of the T105 but will be a hassle with the cabling, this is why I considered 4 of the large capacity. Cost (and freight) is higher on the larger, less available batteries.

[nigel1]

I have just fitted 6 x T-125, same physical size as the 105's, but a few more Ah.
6 at 12V will give a theoretical 720Ah.

[S/V Alchemy]

Originally Posted by laika

I recently ditched 3 group31 AGMs (270AH) for 2 Trojan J185Ps at (410AH). The high profile 185s fit well in my space and actually take up a significantly smaller footprint than the 31s used to.

If you have the height, L16s are also worth a look.

If budget is not overriding priority, why not take some measurements and go with whatever will fit the best for you?

This. You need to add the thickness of the box and any internal or external framing (I would consider L-bar, otherwise known as angle iron, coated in two-part epoxy and welded together save for bolted top bars). The L-16s are generally cheaper per Ah and more robust than the Trojans, which, while a very good battery, are not so much better as to justify their price premium in my opinion. The L-16s have thicker plates and are made for forklift and floor sweeper industrial use. Expect each pair to give you around 400 Ah @ 12 VDC, so four gives you 800 Ah at a weight of about 460 pounds.

If you have that much solar, and say a 100 amp alternator, you won't regret the extra capacity. Recall that the more time spent above the 50% SOC level, the better for the lifetime of the battery. But much depends on how you are able to store them.

Here's an example of a "basic brand" L-16 used in the solar home off-grid world: http://pdf.wholesalesolar.com/batter...ery/RE-L16.pdf

[Debgen]

Industry says your output current of solar panels should be 5% - 13% of total amphr capacity of battery bank. Most use 10% as a rule of thumb.

[wrwakefield]

Originally Posted by Sailorman Ed

I am trying to decide how much battery to add. Based on 530 watts of solar, can can easily fit 4 of the J305E-AC ( 305 AHr) or with difficulty, 6 of the T-105. Previously, we had 270 watts and 359 AHr of gel cells so even 2 of the T-105s are a 25% improvement. We expect to use about 20% more electricity on the new boat. Is 530 watts too much for 450 AHr? The J305 are a 20% premium per annualized AHr/life cycle.

Also looked at the Duracell EGC2 (230 AHr) - they are 20% less than the T-105 and slight shorter ( = less space under the plates?) Gets confusing quickly.

Ed, I've learned [after doing this several time on different boats over the decades...] to go for the maximum amp-hour capacity [and value in both $ and labor...] that fits in the space and budget at hand.

It sounds like your solar charging is suitable [6-7% of bank capacity; 10% the usual thumbnail target...] for either configuration you mention. [43A (I'm assuming regulated solar...) into a 610AH (J305E-AC) or 675AH (T105s) bank.]

As a comparative example, I was able to fit 8- T105s for a total of 900AH 12VDC @ the 20 hour rate. That size house banks suits us well, but I would welcome the chance to increase it if that battery form factor provides such an increase next time around...

Just FYI in case you don't already know (and I didn't until I researched it the time I upgraded my house bank batteries...) Trojan makes a very robust centralized watering system. [Hydrolink]

Let us know how you end up and have fun getting there.

Cheers!

Bill

[Sailorman Ed]

Trojan makes a very robust centralized watering system. [Hydrolink]

- thank Bill, I had seen it and if I go with the T105, I will have to use it due to space. With fewer L16s, I will have full easy access to the tops of the batts

Based on SV Alchemy's suggestion, I am looking seriously at the L16 size, just a bit more $$ and I suspect a much better battery and I can use fewer of them = less cabling. I do have wind (not yet installed) and since I am a cat, I must motor all the time as per the other thread so will pick up some from the alternator. We lived completely on 270 watts of solar last time and a smaller 359 AH battery bank ( 6-7 year old gel cells)

Also per Alchemy's suggestion, will be fabricating a better battery box but the 120 # L16 will take more than me to lift into position.

[ramblinrod]

Originally Posted by Sailorman Ed

I am trying to decide how much battery to add. Based on 530 watts of solar, can can easily fit 4 of the J305E-AC ( 305 AHr) or with difficulty, 6 of the T-105. Previously, we had 270 watts and 359 AHr of gel cells so even 2 of the T-105s are a 25% improvement. We expect to use about 20% more electricity on the new boat. Is 530 watts too much for 450 AHr? The J305 are a 20% premium per annualized AHr/life cycle.

Also looked at the Duracell EGC2 (230 AHr) - they are 20% less than the T-105 and slight shorter ( = less space under the plates?) Gets confusing quickly.

Sounds like you are kinda going about managing your energy needs backwards.

1. Determine how many A-hrs per day you will consume.
2. Determine how many days you wish to go without recharging.
3. Determine how much battery capacity that requires (restricted by space and weight.)
4. Determine how quickly you wish to recharge (restricted by max acceptance rate of battery technology).
5. Select charging system(s) to add A-hrs at rate desired.

Max acceptance at percent of rated capacity:

Standard lead acid (25%)
Gel (40%)
AGM (60%)

Ramblin Rod
Yacht Service Provider
About Sheen Marine

[nigel1]

Regarding the Hydrolink system, I have just fitted this to 6 Trojan batteries, and am impressed with the system, easy to fit and looks good quality.
Because two of my batteries are in a separate location I need to modify the system a bit and needed a second coupler. As Trojan only sell the whole kit, the coupler was purchased from
https://flow-rite.com/
at a reasonable price.

[wrwakefield]

Originally Posted by Sailorman Ed

- thank Bill, I had seen it and if I go with the T105, I will have to use it due to space. With fewer L16s, I will have full easy access to the tops of the batts

Based on SV Alchemy's suggestion, I am looking seriously at the L16 size, just a bit more $$ and I suspect a much better battery and I can use fewer of them = less cabling. I do have wind (not yet installed) and since I am a cat, I must motor all the time as per the other thread so will pick up some from the alternator. We lived completely on 270 watts of solar last time and a smaller 359 AH battery bank ( 6-7 year old gel cells)

Also per Alchemy's suggestion, will be fabricating a better battery box but the 120 # L16 will take more than me to lift into position.

Hey Ed,

It sounds like you are well on your way to a perfect and robust solution for your needs. And you make a good point about the cabling...

Kudos!

Bill

[wrwakefield]

Originally Posted by nigel1

Regarding the Hydrolink system, I have just fitted this to 6 Trojan batteries, and am impressed with the system, easy to fit and looks good quality.
Because two of my batteries are in a separate location I need to modify the system a bit and needed a second coupler. As Trojan only sell the whole kit, the coupler was purchased from
https://flow-rite.com/
at a reasonable price.

Hi Nigel,

I like the Hydrolink system also. It made my expanded house bank possible...

Thanks for the reference to acquire bits and pieces for the system from Flow-Rite.

Cheers!

Bill

[Moontide]

Little bit of 2 cents worth here regarding solar sizing. I would not bother limiting the solar based on the battery capacity. There are some items (watermakers, ice makers, freezers, even our washing machine, etc.) that are nice to run during the day using "excess" solar capacity. Always nice to have the batteries in float mode by noon. Little extra cost for the panels, but in my case the extra juice is usually put to good use.

That being said, I am assuming that the solar controller is 3 stage so it will not burn up the batteries. Would think all "modern" ones are.

Bill