I did not realise that T1 Terry's link could not be viewed. Better late than never !!
This sounds way too good to be true. I will be interested in your comments Terry.
This auction will expire tomorrow so have copied the text from the auction site below. This is the second unit this seller has listed over the last month. There has been some discussion on my NZ forum https://nzmotorhome.co.nz/forum/viewtop
"Buy Now" price is NZ$988.00
Questions & answers
This is the latest generation of 12v 270ah lithium iron phosphate battery(liFePO4). The latest catl cell is used. This is also the safest lithium iron phosphate battery in the world.
5 years warranty.
This deep cycle liFePO4 battery is 12v 270ah. Up to 3kw output.
Deep cycle next generation lithium battery in conventional sizes is finally here! Providing higher energy density than their lead acid counterparts with an added bonus of massive weight saving.
Suitable for RVs, solar energy storage, yachts, automobiles, water pumps. this liFePO4 battery can be replaced directly with the original battery. The circuit does not need to be modified.
This battery is resistant to low temperatures and can work normally in - 37 C.
Our LiFePO4 deep cycle batteries offer high cycle life, higher max discharge rate and can be recharged much faster than lead acid batteries. This range of LiFePO4 deep cycle all include built in battery management system (BMS). The BMS will protect the internal cells from over discharge, over charge and short circuit protection. Providing much higher level of protection around thermal runaway as well as increasing the overall life of the battery.
This liFePO4 battery uses a stainless steel case, which is sturdy and waterproof. This battery is highly safe and supports high-current charging without thermal runaway and fire. It is particularly safe.
reach 80% 80,000 deep cycles times.
bms protection system.
Built-in voltmeter can display voltage at any time.
Automatic overload protection.
Install independent 3A equalizer to support high current automatic equalization.
short circuit protection.
Continuous discharge current reaches 180 amps. Can be used for car, truck engine start, discharge CCA up to 2000cca
Charge voltage: 13.6-14.9V
Float voltage: 13.6-13.8V
Cut-Off Voltage: 10.8V.
LiFePO4 (LFP) chemistry
Discharge operating Temp : -37 to 65 C
Please click here to ask a question
Auckland (Excl Waiheke Island & Others)$20.00
North island NON RURAL$20.00
North island RURAL$30.00
South island NON RURAL$30.00
South island RURAL$35.00
Store allows pick-ups
Store location: Auckland City, Auckland, NZ
Cheers and "Merry Christmas" Chris
Reply by T1Terry !!!
A couple of things say this is B/S wrapped in technospeak. 100Ah @ 0.5CA discharge rate weighs min of 16kg. These batteries claim to have a stainless steel case so that would make them even heavier. This means a genuine 250Ah LiFePo4 battery would weigh at least 40kg, this thing weighs 28kg.
The claim is the battery can handle -37*C and still operate as normal ... this is total B/S unless it was built with a special electrolyte mix, but then it wouldn't be able to handle the 65*C. At house battery discharge rates of 50 amps per 100Ah capacity, the operating range is 0*C to 60*C for LiFeP04 chemistry and -20*C to 65*C for LYP chemistry cells. The cell won't be destroyed at -37*C, but you can't attempt to discharge or recharge at anything more than a trickle rate at those temperatures, maybe 10 amps per 100Ah max, so not a normal LiFeP04 charge or discharge rate.
The cases are claimed to be stainless steel, this one is a real scary item. The metal cases develop a voltage and this needs to be isolated from any other metal surface that could also have a voltage or tied to the battery negative. A member of the local AEVA had his Prius burn to the ground due to the insulation between the cells and the body failing. The arc produced burnt a hole through the aluminium battery tray, it was that much of a short circuit.
The charging upper voltage of 14.9v is to make it look like they are lead acid drop in replacements, but 14.9v would equal 3.75v per cell in a perfectly balanced 12v battery. Anyone who is experienced with using lithium batteries knows as soon as the cell voltage goes over 3.6v it starts to rapidly run away. All the cells reaching 3.6v at the same time, every time, is just never going to happen, to reach 3.75v all at the same time, yeah right .... The claim it can shift 3 amps from cell to cell isn't much use if the charge rate is higher than 3 amps, one cell will run away to the point of destruction.
Simply by weight, this battery would be less than a genuine 170Ah @ 12v, probably more likely a 150Ah battery. The continuous 180 amp discharge would be a little more than a 1C discharge rate if it was a 170Ah battery, a 1.2CA discharge rate for a 150Ah battery, both well within the capabilities of any decent LiFeP04 cell or battery.
In reality, this battery is $6.50 per AH @ 12v, can not have any of the cell links cleaned during its service life, nor can it have any individual cell replaced if needed. A replacement 160Ah Winston cell would be about $320, not $988 if a cell failed resulting in the whole battery headed for the rubbish bin.