rockylizard wrote:

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T1 Terry wrote:

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As far as the 12.7v being 100% SOC for an AGM battery, can't agree and neither does the manufacturer if you check the chart, they start at 13v, after 1 hr @ a constant 6 amp load it looks to be somewhere around the 12.7v mark but that means 6Ah have been drawn from the 100Ah battery, so to me that indicates 12.7v represents around 94% charged (100 - 6 = 94)
As far as the 12.06v representing a caution voltage, no idea if this is while under the 6 amp load or rested and the manufacturers battery battery chart doesn't mention it either so......

The whole thing about only discharging to 12.4v for a longer life has me a little puzzled, are you actually drawing 20Ah @ 6 amps from each 100Ah battery or is this just a guestimation based on a voltage test... again, rested or under load? What I'm saying is, if you are only drawing a total of 40Ah over night then why use 2 batteries? A good 100Ah AGM battery should provide 40Ah over night if the load is only 6 amps max and do that for 600 cycles (600 over night discharges) which would equal quite a few yrs of ownership. So where is the value in 2 batteries doing the job one battery should be able to do without a problem? Twice the purchase price, twice the weight and twice the space taken up..... how much will it cost to replace the two batteries when the time comes to replace them?

T1 Terry

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Gday...

Jest sayin' Terry. Ya gotta get to actually reading, understanding and retaining what posters say before you begin your torrent of advice. 

I have only ONE 120Ahr AGM and my 4 to 5 hours of power usage overnight reduces my ONE 120Ahr battery from 12.7V SOC as shown on solar controller to around 12.4V SOC when I rub the sleep from my peepers about 6.30am of a morning.

My solar panels then restore the battery to a float charge of 13.4 (through bulk and absorption) before lunchtime ... which they hold the battery at until the suns sinks slowly in the west . This has now been happening with boring repetition for about six years now.

I am fully aware you are deeply involved in Lithium sales, installation and service ... but if you want to maintain a credible reputation as an adviser on "all" battery systems, you need to temper how you read and interpret what users already have and need ... and then tailor your advice to what their ACTUAL needs/requirements are rather than your opinion (and potential cashflow requirements) thinks they should have.

Cheers - and thanks agen - John

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Hmmm..... you jumped in and quoted something addressed to someone else and I can't see where you actually mentioned that you have only one AGM battery, so the "Batteries as pets" clearly wasn't typical of your useage and I apologies for what ever I said that has upset you.

Just as a matter of interest, if the majority of your energy storage comes from LPG, how much per yr does it cost you if you live 24/7 on the road in your van and free camp the majority of the time? Please correct me if I've miss interpreted that assumption and please don't take it as an attack, it is not intended that way but rather as a cost analysis over time.

I have always said that those who only move from mains supply to mains supply really have no use for a lithium battery set up and I question if a battery is required at all for such a use pattern. But you have put forward a use pattern I am not familiar with so a cost analysis would be useful to those who feel they may have a life style that matches your use pattern.

As far as making money when it comes to lithium batteries and RVs, T1 Lithium would be much better off sorting poor installs than actually designing and supplying, then it wouldn't have the obligation to provide tech support for the life of the system and warranty for any products supplied .... but that would hardly be fair because people would not have the option to get it done by us the first time with far less problems and a clear path for problem sorting they can be guided to do themselves via labelled photos and supporting emails. We would really be setting ourselves up to profiteer from those who fell into the trap of DIY because they thought they had no other option and that isn't the way I tick.

 That sort of sounds like if you don't get T1 Lithium to do the job then it won't be done right and that is not what I mean. There are companies out there that can actually do a decent lithium install, there are those that make it look super simply for a DIY install and lure unsuspecting folk into a rather expensive down hill spiral, I just attempt to advise that there are better options than lead acid batteries or drop in lithium batteries if their energy use patterns indicate it would be a better option.

T1 Terry   

T1 Terry wrote:

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Hmmm..... you jumped in and quoted something addressed to someone else and I can't see where you actually mentioned that you have only one AGM battery, so the "Batteries as pets" clearly wasn't typical of your usage and I apologies for what ever I said that has upset you. Not upset, just find opinions pushed down one's throat tiresome.  I simply suggest you go back and read my earlier posts. 

Just as a matter of interest, if the majority of your energy storage comes from LPG, how much per yr does it cost you if you live 24/7 on the road in your van and free camp the majority of the time?  Just calculated it ... about a 9Kg bottle per month - so probably between $350 and $400 per year - depending on how much cooking, and water heating, I do on the open fire. 

T1 Terry   

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 Gday...

I have absolutely no issue with lithium as a product and I have read and heard sufficient to realise it has excellent capabilities for those who are off the grid 'full-time' AND have high power usage to complement their 'comfortable' lifestyle. It is just it would exceed the needs for my lifestyle and the cost, for my circumstances, are prohibitive.

The 'hard sell' that accompanies any mention of AGM usage by travellers becomes wearing. It definitely not, at this time of my life and at this time in my journey, the best outcome to contemplate given the considerable outlay to lithium. 

Cheers - John

T1 Terry wrote:

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Think I'd believe the manufacturer rather than a battery reseller, http://www.fullriver.com/products/admin/upfile/DC120-12B.pdf first chart on the right hand side, 6 amp discharge line is close enough to a C20 discharge rate, it gets much worse at a higher rate as you will see from the chart. Start voltage is 13v, at around the 10hr mark or 50% of a 20hr discharge, the line crosses the 12v mark. To me that says fully charged is 12.8v or better and 50% SOC is 12v.

As far the voltages and SOC for LiFeP04 batteries, who ever gave you those figures hasn't got a clue, you can not gauge an LFP or LYP battery SOC from terminal voltage over 4 cells, only fully charged or fully discharged by individual cell voltages. 0% SOC can still be better than 3v per cell in an LFP or LYP cell so 4 perfectly even cells would add up to 12v or more yet the full 100% of the advertised capacity had been used. An LFP or LYP cell should never be discharged lower than 2.8v but that is not the same as 0% SOC, it does mean the cell is now totally drained of all its capacity though and tat could mean more than the advertised capacity has been drained from the cell....... a whole different world to lead acid technology, the only thing they have in common is 13.8v represents approx. fully charged for a 12v battery, but that goes the same for both lead acid and LFP/LYP batteries, only the cell voltage tell the tale for Li and specific gravity for lead acid

 

T1 Terry

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 As you suggested Terry, I think that I will go with the Manufacturer rather than the Battery Reseller, oops, but your a Battery Reseller aren't you Terry?

Kebbin wrote:

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T1 Terry wrote:

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Think I'd believe the manufacturer rather than a battery reseller, http://www.fullriver.com/products/admin/upfile/DC120-12B.pdf first chart on the right hand side, 6 amp discharge line is close enough to a C20 discharge rate, it gets much worse at a higher rate as you will see from the chart. Start voltage is 13v, at around the 10hr mark or 50% of a 20hr discharge, the line crosses the 12v mark. To me that says fully charged is 12.8v or better and 50% SOC is 12v.

As far the voltages and SOC for LiFeP04 batteries, who ever gave you those figures hasn't got a clue, you can not gauge an LFP or LYP battery SOC from terminal voltage over 4 cells, only fully charged or fully discharged by individual cell voltages. 0% SOC can still be better than 3v per cell in an LFP or LYP cell so 4 perfectly even cells would add up to 12v or more yet the full 100% of the advertised capacity had been used. An LFP or LYP cell should never be discharged lower than 2.8v but that is not the same as 0% SOC, it does mean the cell is now totally drained of all its capacity though and tat could mean more than the advertised capacity has been drained from the cell....... a whole different world to lead acid technology, the only thing they have in common is 13.8v represents approx. fully charged for a 12v battery, but that goes the same for both lead acid and LFP/LYP batteries, only the cell voltage tell the tale for Li and specific gravity for lead acid

 

T1 Terry

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 As you suggested Terry, I think that I will go with the Manufacturer rather than the Battery Reseller, oops, but your a Battery Reseller aren't you Terry?

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:lol: No, we won't actually sell anyone a lithium battery, we custom design and manufacture lithium systems built from raw components and back that system with support for the life of the system.

We do resell AGM batteries that still have a bit of life left in them where someone living in an on site shed or caravan that needs a very basic power supply while building their house or wants one for a trolling motor used an hr a day for the Christmas holiday break..... but we sure don't tell them how great these batteries are  These were replaced with a lithium battery system at the request of the RV owner for a reason, they didn't do what the owner required.

Talk up AGM all you like, they do suit a small section of the leisure battery market, but in general they are using a technology that is now far out dated based in the 19th century.  

T1 Terry

T1 Terry wrote:

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Aus-Kiwi wrote:

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I can purchase a whole battery pack for the price of some high end battery .

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and??? I can sell you heaps of labelled Ah battery storage cheaper than you can buy them, but that doesn't actually mean you paid a good price per useable Wh of battery storage or a set up that is cheap to maintain, efficient or small/light enough not to cause problems. $$ per useable Wh over the cycle life of the battery, the true comparison of apples with apples, it is the technology used in your phone and computer for a reason  

 T1 Terry 

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 Hi Terry

As usual you do not know when to stop in your quest to dominate every discussion. The technology in your phone and computer is not the same. Indeed I believe you argued this some time back ? Give it a break and you might help your cause !

Jaahn