Have to Upgrade My Battery Bank - Acid or Lithium ?

[ebaugh]

Originally Posted by randude

I will look at your sources as my customer really wanted to explore a safer and greener battery. Weight is a concern of mine, I suppose that makes me unique here. Power is also a concern, although when underway I have plenty of DC. Some of these guys with inverters could solve some of my problems if I can get beyond the cost. I will check out your source and do a true life cycle cost analysis. I am a bit irritated with the company in Canada, they were in no hurry to help me, and really don't seem too disappointed in my breaking away from them.

Good luck! There will be no competition on weight. That's a huge benefit to LiFePO4. I replaced 792 lbs of lead with 336 lbs of LiFePO4 with greater usable capacity. I don't know if it's greener, but I think at least equally safe.

[T1 Terry]

Just found this thread, you think the other lithium one takes some twists and turns... I'm no longer sure what the question was
I have changed to calling the cells lithium ferrous, saves any confussion with lithium polymer that way, lithium iron and lithium ion are just to similar and mis understands start flowing from there.

A personal example, I have 1 x 500ltr fridge freezer (18 cu ft) and 2 250ltr fridge freezers (9 cu ft) running from inverters powered by 720Ah @ 12v of Winston Batteries lithium ferrous cells. They have been running 24/7 for the last 12 mths recharged by nothing but solar so they have absorbed up to 3 days without much sun. These cells also power a Waeco 60 ltr esky type beer fridge and all the led lighting on our back patio and the controller and recirculation pumps for the 300ltr solar hot water system. These packs were built up from single cells purchased in a box, no special measuring for matched cells and no BMS accept for a Junsi cell logger that records cell voltage and set off an alarm if one goes high or low.
I have sounded the alarm on high cell voltage a few times, my fault messing with stuff, the inverters have shut down on low voltage (10.5v) a few times after a week of rain, capacity tests have shown they are still at over 720 Ah capacity after each time and now after 12 mths use. The last charging graph shows at the end of peak charging the cells drifted to 28 milli volts appart but settle back to 11 milli volts, needing a BMS to stop cells difting appart is possibly a stretch of the truth, these have had no BMS balancing or manual balancing in 12 mths continuous use.

I have also assisted via email etc a number of people around the world as well as within mainland Australia to set up 100% off grid house power systems. My knowlege is based on fixed and mobile home units, caravans (trailers?) etc but as far as house power goes it all seems to cross over to boats without too much difficulty. My knowledge is both trouh reading and putting the theories to hands on experiments and logged tests, there is a lot of nonsense out there passed off as fact.

As far as some of the comments about Chinese knock offs, I think you will find modern day knowledge and build capabilities it's the other way around, these people have put in the yards and know how to build good stuff now. Winston, Sinopoly, both brands with a lot of knowledge behind them, A123 is sort of up there but cylindrical cells are their claim to fame, not so much the prismatic cells that are the ones suitable for house battery use because they have the capacity, EV type applications need the instant current so cylindrical cells shine in that application.
GBS have more recently hit the market with a slightly different chemical make up, yet to get the runs on the board but they show a lot of potential.
Balqon is Winston Batteries US distributor arm so they will have the best prices with no problems regarding self importing etc or waranty issues.

If you have any questions I will attempt to help you, I don't do this for money, I don't even sell the things, just hate to see incorrect information trying to be passed off as fact.

T1 Terry

[haiqu]

Originally Posted by ebaugh

Lithium is coming down in price....at least one example:

It's been posted before...but Balqon recently started distributing Winston lithium phosphate cells in the US. They are advertising a 1000 AH 4 cell pack 12.8 V pack for $3450 and 700 AH for $2640. Since 70-80% of capacity is usable, that's probably less than AGM today.

Just priced AGM batteries for a possible electric drive install. 210AH 12V batteries are available for $389. If I needed 700AH then this might make sense, but I still wouldn't like to have to buy four of them for a 48V system.

Regardless that 70% of the stated capacity may be usable they still need to be recharged, and a 700AH system will have to be recharged either from a stand-alone generator or an alternator on the auxilliary motors (assuming a yacht). Therefore they don't need to be discharged to 30% capacity and so a cheaper AGM will suffice, at 40% of the cost.

The figures provided only make sense on a vehicle that doesn't carry it's own means of recharging, i.e. an electric car or a boat that's a dock queen, sans generator.

Also can't fathom the number of people on this thread using 110v or 240v refrigeration via inverters. Apart from the extra cost of the inverter, you're throwing away 10-15% efficiency right there, not to mention the added maintenance issues.

Rob

[T1 Terry]

Also can't fathom the number of people on this thread using 110v or 240v refrigeration via inverters. Apart from the extra cost of the inverter, you're throwing away 10-15% efficiency right there, not to mention the added maintenance issues.

For me it was because I couldn't see the logic in paying thousands more for a far less efficient refrigerator/freezer. The Australian standards cover efficiency of refrigeratot freezers sold in this country, they have strick performance guide lines they must meet before they can qualify for a star rating on their efficiency. In the RV game there aren't any low voltage upright fridge/freezers that can pass the 43 deg ambient test so they don't even qualify for a star rating. Efficiency in power usage needs apples to be compared with apples, when you can find a low voltage fridge freezer 250ltr or bigger that can pass the AS/NZS 444.1:2010 standards test then a power use comparison can be made but not before.
In real world testing, a well established brand name 212 ltr fridge freezer side by side with my Fisher & Paykel E249T fridge freezer. The E249T complete with auto defrost used 79Ah @ 12v nom average over a 30 day test including inverter losses, the low voltage unit average 82 Ah over the same period and fail the 3 ice cube test.

T1 Terry

T1 Terry

[Lagoon4us]

Originally Posted by T1 Terry

For me it was because I couldn't see the logic in paying thousands more for a far less efficient refrigerator/freezer. The Australian standards cover efficiency of refrigeratot freezers sold in this country, they have strick performance guide lines they must meet before they can qualify for a star rating on their efficiency. In the RV game there aren't any low voltage upright fridge/freezers that can pass the 43 deg ambient test so they don't even qualify for a star rating. Efficiency in power usage needs apples to be compared with apples, when you can find a low voltage fridge freezer 250ltr or bigger that can pass the AS/NZS 444.1:2010 standards test then a power use comparison can be made but not before.
In real world testing, a well established brand name 212 ltr fridge freezer side by side with my Fisher & Paykel E249T fridge freezer. The E249T complete with auto defrost used 79Ah @ 12v nom average over a 30 day test including inverter losses, the low voltage unit average 82 Ah over the same period and fail the 3 ice cube test.

T1 Terry

T1 Terry

What inverters do you use Terry?

[noelex 77]

Originally Posted by T1 Terry

The E249T complete with auto defrost used 79Ah @ 12v nom average over a 30 day test including inverter losses,

in my experience the domestic fridges are considerably less efficient than a good 12v boat fridge.
Your figures of 79AHrs is a large consumption for a boat fridge, but is still better than I would have expected with this type of fridge.

He goverment testing lists the consumption at 691kwHrs a year, which allowing for even a very slight inverter losses is about double the consumption that you are measuring.

The goverment test is a reasonably high ambient temperature, but typical of a boat in summer, particularly around the coils.

I would caution people that there power consumption may be considerably higher than you are finding with your installation.

[ebaugh]

Originally Posted by haiqu

The figures provided only make sense on a vehicle that doesn't carry it's own means of recharging, i.e. an electric car or a boat that's a dock queen, sans generator.

Also can't fathom the number of people on this thread using 110v or 240v refrigeration via inverters. Apart from the extra cost of the inverter, you're throwing away 10-15% efficiency right there, not to mention the added maintenance issues.

Rob

You can buy 100 or 200 amp hour cells at the same place. Cost about $4 an amp hour at rated capacity for 12.8V. So let's round, AGM at $2 amp hour. You get 50 usable amp hours with AGM versus 70 with LiFePO4. Looking at it this way, it's $4 per usable amp hour versus 5.7 for AGM. It's more until you compare the cycle life should be at least double. Then if space and weight are an issue it will fit in 1/2 the space, and weigh 1/2 or less the weight for the same usable capacity.

The recharging issues are moot, whatever you use, you have to put back, regardless of the battery chemistry.

You are correct about the losses in refrigeration efficiency. The compressors are less efficient, plus conversion losses. But I'm not so sure about the maintenance. I'd have the inverter anyway. Always have, even on my previous 2 30 footers.

I don't like my current refrigeration for full time cruising off grid, but I have 4 110V home style units with a combined 10 cu ft freezer and 10 cu ft refrigeration, 20 cu ft overall. Total replacement cost is about $1500 for all of them, try doing that with marine 12V powered units at anywhere near the same cost. Most of the cost was the ice maker unit....but if one breaks, you just buy a new one for $200 or so and slide it in. maintenance could not be simpler.

[ebaugh]

Originally Posted by noelex 77

in my experience the domestic fridges are considerably less efficient than a good 12v boat fridge.
Your figures of 79AHrs is a large consumption for a boat fridge, but is still better than I would have expected with this type of fridge.

He goverment testing lists the consumption at 691kwHrs a year, which allowing for even a very slight inverter losses is about double the consumption that you are measuring.

The goverment test is a reasonably high ambient temperature, but typical of a boat in summer, particularly around the coils.

I would caution people that there power consumption may be considerably higher than you are finding with your installation.

I use about 400 AH daily for 20 CU FT in the Caribbean. But it's 1/2 freezer space and 4 units including an ice maker. If you take out the ice maker, it would probably be 250 AH daily for about 17 CU FT. Still more than Terry's numbers, but probably more freezer at 7 cu ft.

[ebaugh]

Terry, You may have said, but how many watts of solar panels do you have for the stated system?

[T1 Terry]

Originally Posted by noelex 77

in my experience the domestic fridges are considerably less efficient than a good 12v boat fridge.
Your figures of 79AHrs is a large consumption for a boat fridge, but is still better than I would have expected with this type of fridge.

He goverment testing lists the consumption at 691kwHrs a year, which allowing for even a very slight inverter losses is about double the consumption that you are measuring.

The goverment test is a reasonably high ambient temperature, but typical of a boat in summer, particularly around the coils.

I would caution people that there power consumption may be considerably higher than you are finding with your installation.

The E249T has a govt test figure of 387kWhr/yr, marked on the label, that works out to 81.5Ah per 24hr period with a battery voltage of 13v, lithium ferrous batteries will maintain 13.2v or better till they are well discharged.
The AS/NZS 4474.1:2010 requires the test to be in still air with an ambient of 38 deg C (100degF) constant, no over night cool down, the test for performance is from 43 degC (110 degF) heat soaked down to minus 15 degC (5 degF) in the freezer and 5 degC (41degF) in fresh food section in 16 hrs in still air, they don't take an energy reading for that though, I'd guess it would be close to a 100% cycle rate to achieved that, impossible for anything but a custom built low voltage unit. The figures on the Australian Standards label can be taken as a realistic example, add 10% for inverter losses to be on the safe side but if you were planning an off grid set up you would be carrying a min 2 1/2 day energy storage in the battery pack or a method of generating enough power to meet the immediate requirements and recharge the battery pack with in a 12hr period. It would be a game of Russian roulette otherwise.
On a boat you would have the benefit of a water cooled condenser available, that would drop energy use considerably, RV’s are stuck with the ambient temp plus heat soak through the windows. The worst I’ve had was 118Ah per 24hr period under a corrugated iron roof and closed in verandah in mid summer, gets a tad warm around these parts in summer, I needed to know it would work before I fitted it into the bus conversion so I tested it myself.

T1 Terry

[T1 Terry]

Originally Posted by Lagoon4us

What inverters do you use Terry?

The ones I'm using at the moment are a cheap E Bay purchase 1000w PSW and a J Car 1000W PSW about 5 yr old, can't buy them any more unfortunately. the bus will have a Victron Quattro although I am trialling a Tawian import from E Bay that works suprisingly well for a lot less $$ but in a boat I'd go the Victron any day, a proven product.

T1 Terry

[T1 Terry]

Originally Posted by ebaugh

Terry, You may have said, but how many watts of solar panels do you have for the stated system?

All up around 2 kW of solar but not all of it gets sun all day, big trees and a house each side of me

T1 Terry

[noelex 77]

Originally Posted by T1 Terry

The E249T has a govt test figure of 387kWhr/yr, marked on the label, that works out to 81.5Ah per 24hr period with a battery voltage of 13v.

I am not sure why are figures are so different.
I have double checked the model and the E249T it is listed at 691kwHrs/year.
I even found this blog. Where someone tested himself and got 722KwHrs/year.

How Bad is My Fridge? The Results « Energy Efficiency Blog

Maybe Fisher and Paykel made two differnt models with the same number?

[T1 Terry]

An N249T was up around those figures but the E249T checks out on the Australian standards website as 387kWhr/yr http://reg.energyrating.gov.au/comparator/product_types/28/search/?wrapper_search=&machine_type=Two+Door+Fridge%2FFr eezer&capacity=200to300&brand_names=fisher+%26+pay kel&multiselect_id_brand_names=fisher+%26+paykel&m odel_number=&paginate_by=20&expired_products=on
If you check out that website you will notice that the Fisher & Paykel is not the top rating model either, there are even more efficient models out there now.http://reg.energyrating.gov.au/comparator/product_types/28/search/, the Electrolux 517ltr 2 door uses even less. Refrigeration has come a long way in very short time and is getting better all the time. The benefits of a water cooled condenser would reduce those figures even further but then it's not an "off the shelf" unit. The new models using propane as a refrigerant are a lot better. A leading brand starting with S was busted for cheating the test by writing a program that identified when it was in test mode and changing the cycle pattern, the test has now been updated to include a number of door openings to simulate every day use better, it didn't effect most makers, the test load packs act as a fully stocked fridge and freezer so they effectively store the cold, very little is lost, only a small amount of air change really and air is easy to chill. The E249T went up from 387kWhr/yr to 394kWhr/yr, the L & T signify left or right hand opening door, the S is for stainless steel outside rather than white painted.

T1 Terry

[randude]

When it comes to refrigeration on a boat the keys are conservation and insulation. There are some creative ways you can come up with and very thick insulation should always in the plan. Then don't open it a lot. You plan your trips to the frig and open and close the doors quickly. You store things in there in a logical and repeatable way to reduce door-open time. Just google frig techniques and efficiency and you will come up with some ways to save energy. These forums are great places to learn better ways and discuss them.