Solar system batteries-Is Tesla Powerwall working

[Malapuaao]

Seems like my bank of 8 L16 Interstate batteries only last 3 years at best, I don't know why other people are getting by on longer by this is my third set at 3 years.

I'm looking into alternatives and the Tesla Powerwall sounds ok, 14kw for $6k.

Has anyone had any success or failure with a Tesla system on an Outback?


aloha

[Tink]

Found this good reading on battery life.

http://www.mpoweruk.com/life.htm

Community begins with Aloha

[Carey]

LG Chem now offers a 9.8KW LI battery.... Do not know the life, as we are waiting for the installation, but there is now a wall mounted choice...

[kalakoa]

I have 6 years on a set of L16.

Powerwall isn't really "available" without installation by professionals as part of a new system that's designed to be compatible with the high voltage (350VDC).

If you're replacing your own batteries, try the Outback 200NC, adjust charge controller to match.

[Peter Epperson]

http://simpliphipower.com/

[kalakoa]

Does anyone actually stock LFP on-island?

[bluesboy]

my batteries are ready for a replacement too. i have four L16s that lasted almost four years, but they were my first set.

i'm gonna double up to 8 batteries (I have 8 260w panels). i'm considering either agm or lead-acid. what's better?

i'd consider the outback, but aren't familiar enough with them to feel comfortable going there.

[kalakoa]

Outback NC are basically AGM with some proprietary enhancements, set the charge controller for GEL and enjoy the maintenance-free...

Each battery is 12V/200Ah, so the array layout is slightly different, but they include a connecting bar for the series hookup. Documentation suggests a "cross-corner" feed to equalize the battery cable resistance, and no more than 3 strings in parallel.

Currently about $450/each at Gexpro.

[kander]

Battery life is highly dependent on how the batteries are treated through their lifetime. Its not impossible to get 12 or more years out of a battery bank.
Lifetime of the battery can greatly be shortened by three factors. Failure to maintain and keep water levels correct, having too small of battery bank to satisfy needs without discharging the battery too far and causing excessive damage and finally, not getting the batteries fully floated by the time the next discharge cycle comes that night.

It seems a lot of folks dont realize these things. Maintenance and correct electrolyte levels in the battery is a given, you either watch them like a hawk or you might forget and let them get low on water. This over time drastically enhances the secondary effect.
Lead acid batteries (and most others) have limits to the amount of power that can be pulled from them before the plates start building lead sulfate crystals that fall off (plate erosion) or can cause shorting out of the cells.

When a lead acid battery is discharged more than 60% of total capacity the batteries are starting to take damage. This means that taking a 12V battery below 12.24V (24.48V or 48.96V systems) is causing harm to it. 12.10V is considered the 50% and is most certainly shortening the life of the battery. A lead acid battery is considered dead at 11.7V

These batteries are rated in Amp Hours, from full to zero, so if you have a 400Amp hour (AH) battery bank, you can only pull 160AH from it before your damaging the batteries.

AGM and Gel also aren't without their drawbacks and also take damage from being discharged too far or not being charged back up correctly.

LiFePO4 batteries will provide a much longer service level for storage, the amount of power pulled from them also effect the lifespan of the batteries, but instead of a few hundred discharge cycles you have 5000+ and only loose 30% of your total battery capacity over that time, and again another 30% of that amount after the next 5000 cycles. Lifepo4 in theory should be about the last battery bank you ever have to buy.

[Peter Epperson]

Once again, this seems like the answer https://www.youtube.com/watch?v=jj83sQ_kAyM
Aloha lead acid, no love lost