Choosing a Home Battery

Caban
Super Nova
2 Replies 2745 Views

Buying a set of batteries for your home is a big investment and there is a lot of choice out there. It is also probably a better purchase to benefit the environment than buying an EV.

 

I have had batteries on my house since early 2014. Now on to my second (and final) set. First set were Deep Cycle Lead Acid that was all that was affordable at that time. I expected 10 to 12 years from them but, due to other problems, they only lasted 6 years. It only took one cell in one battery to fail and the whole lot needed to be replaced. This is one of the big failing of Lead Acid in that you cannot change out one faulty battery. They also are not tolerant of deep discharges and do not have a great lifespan.

 

When they died I needed to replace them. I was already looking into this and was interested in some Nickel Iron cells. The drawback with those was the high internal impedance, especially when cold. So putting on the Kettle and Toaster on a frosty morning can result in a blackout or switching back to grid. At this time the Musk Stick was promoting the LIon sets. I considered those, and they are also the most popular choice now, mainly due to their being used in all the EV's. They have a distinct advantage for mobile applications as they are very energy dense, so less weight for the power delivered. For a home installation they do have some problems where the density is not an advantage. They can suffer from Thermal Runaway and result in a fire which is almost impossible to extinguish and their lifespan is also not the best.

Looking around I found the cells which tick the most boxes were the LTO Cells (Lithium Titranate) which I now have installed. They use Lithium but in a much more stable chemistry. They do not have  thermal runaway issues and have a very long lifespan. The lower density is not an issue in a static installation.

The set I have should last longer than me, with an expected life of 50+ years and a warranty of 20 years that they will be better than 90% of new capacity. At the time I made the purchase these batteries were about the same price as the LIon cells, but they have come down a bit since. I still think the LTO are better value as they have many advantages over other cells.

If I had the funds I would increase the capacity of my batteries. I currently have 4 x 1.93 KWh = 7.72 Kwh but I would like to make it 6 units and 11.58Kwh storage.

 

What have you got or are looking at?

7 REPLIES 7
thunter
Conductor
1 Reply 2736 Views

Went off the boil for a little while trying to judge the right time to buy. At present I'm looking at a SunPower 10.1kwh LIon. What are your thoughts on V2H?? Have you tried any VPPs?

David_AGL
AGL Community Manager
2 Replies 2734 Views

@John-T you've got batteries, correct? What did you go with for your setup?

Caban
Super Nova
0 Replies 2724 Views

@thunter 

 

I do not have an EV and that will not change for a while, until they become a more viable proposition. I could explain my logic but that would be similar to the reasons in this Video (Careful - Sarcastic Content)  That is why I do not have V2H (Vehicle to Home) but if I went down the EV path it is an option I would consider. At present I drive a manual diesel car which is very efficient and has a lower carbon footprint than an EV charged from the general grid mix.

 

My Inverter and Power Management  system does not support VPP (Virtual Power Plant) but I chose an Australian Made unit of high quality and well supported. My aims are to preserve as much self generated power as possible and then use the FiT to off set the Grid Connection Ransom Charge.

John-T
Powerhouse
1 Reply 2619 Views

Hi @David_AGL 

 

I have a Tesla Powerwall 2 - 14KW Battery, 13.5kw usable.

Fronius 8.2Kw Inverter

8.58kw in Solar panels

 

It has served me well.

 

I recently took delivery of my 2023 Camry Hybrid which puts a pure EV to shame 50ltrs will get me from Sydney to Melbourne with a touch to spare, "TESTED"

It has an extremely lower carbon footprint than an EV as far as i am concerned. 😀

 

Kind Regards

John

 

 

Plan:   Solar Savers

Dist:    Endeavour Energy

State:  NSW 

John-T
Powerhouse
0 Replies 2606 Views

@David_AGL 

 

My apologies for the late reply, I was out of town.

 

Kind Regards

John

Caban
Super Nova
1 Reply 2603 Views

Hi @John-T 

 

How much was the Musk Stick Wall? How long to break even? When will the cells need to be replaced?

 

My car is only ICE but will go from Lismore to Sydney and back to Taree (1100km "TESTED") on the same size tank, with a 5 liter reserve. If required it can still accelerate from 0 - 100 in 7.2 secs. Best economy I have recorded on a trip is 3.4 l/100 from Ipswich to Byron (no hills). Around town it will normally run at about 5.2 l/100. Pity it's a model which has been discontinued.

 

John-T
Powerhouse
0 Replies 1462 Views

Hi @Caban 

 

Sorry for the late reply,

 

I have been dealing with some issues interstate.

 

I was very lucky in that I got my PW2 Musk Stick before they shot up in price,  It was about 11K, I have had it for 2 years current degradation is approx 5% which is pointing at a 75% total capacity at the 10 year mark.

 

Comparing previous power bills and as to when it pays for itself is a little harder as I got the whole system installed once I bought my new house. But if I were to compare to my old power bills at the old address then I have already paid off my Panels and Fronius Inverter 8.2Kw, Panels = 8.58Kw it is a 3 phase system another 3 - 5 years and everything is paid. We were getting bills up to 1400 a quarter.   

 

Again this is not exact and I am doing a lot of guess work but you get the drift. It pays.

 

Those are some very nice consumption figures you have there, They are comparable to my hybrid though I do slightly better in city driving.

 

Kind Regards

John

 

   

Plan:   Solar Savers

Dist:    Endeavour Energy

State:  NSW