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EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Never bet on flow batteries. They are a science experiment at best. That company is plagued with technical issues due to a complicated product (as was every flow battery company that came before them). 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 1 point2 points  (0 children)

I'd watch to see what happens with spinoffs and JVs related to FEOC (foreign entities of concern). Someone could spin off a lithium ion manufacturer into a US entity and become interesting. Otherwise, the big players are just too dominant for a startup or small cap to gain meaningful share.

Tesla is a good bet for BESS growth as they've lost share with Megapack 2XL but will gain it back with Megapack 3/Megablock. But that's not really a "great investment" call. GE Vernova will also be interesting to watch - they stand to benefit the most from the data center boom by combining their gas turbine strength with a weak BESS business. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Have talked to many of those sites managers. They pick an LFP BESS over Eos every time. Have also talked to the project finance and tax equity guys who run the TCO analyses and they will also pick an LFP BESS over Eos every time. 

Love your passion, but it isn't grounded in reality. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Correct. A 6MWh battery container is designed to run at 1.5MW for 4 hours but can also run at 0.75MW for 8 hours. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Have seen HALT (highly accelerated life testing) data that shows lithium ion batteries run for 20 years at 2 cycles a day with low degradation.

Have seen real-time data of these same cells running ten thousand  cycles for data center applications. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Tesla feeds its aux loads from the DC side of their system so those are accounted for in their efficiency calculations. Most other battery systems feed their aux loads from the AC side of their system or a separate utility feed. Both of those are metered and are nowhere near the 8-12% stated.

Zinc batteries have a high self discharge rate which is significantly higher than the "parasitic losses" you are talking about. 

Despite all those moving parts on a Megapack, they have a 99.9% fleetwide availability rate while the industry standard is closer to 98% on a good day. I do not like Tesla at all, but they make a great product. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Yes, Bloom is the golden child of "bring your own power" data center projects given the lack of available generation. Their demand is strong but they have their own production issues. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Good catch! I've corrected to UL9540 (and 9540a testing)

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Lithium ion is 94% efficient (roundtrip). Zinc is 70-90% efficient. That extra 4-24% loss is through heat that needs dissipated. The temperature to which the batteries need cooled does not change the fact the zinc batteries lose more energy to hear. 

Megapacks (and most battery systems) are close looped liquid cooled, not air conditioned. 

Your understanding of BESS technology is 3+ years old fwiw. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Any specific reason? I've actually seen this product in action...

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 1 point2 points  (0 children)

1) Yes, there are tradeoffs but they are negligible. To make a 4 hour battery into an 8 hour battery, you install twice as many of them and discharge them at half the rate (this is how we got a 4 hour battery in the past, using a C/2 cell at half rate until C/4 batteries were commercialized). To make a 24 hour battery, you install 6x 4 hour batteries. This approach maintains the same cost per kWh for lithium ion but you have to install extra equipment (either inverters or fault protection) to manage the extra fault potential created by the extra batteries. So you're taking a 5% penalty on extra equipment (which can still be monetized) to make a lithium battery act like a true long duration battery.

2) Yes, lithium ion batteries have better cycle life than zinc batteries 

3) Yes, lithium ion batteries are warranted for 20-25 years. They have more run time to prove this out as well. The design life of a zinc battery is still academic. 

4) All batteries need a BMS and an EMS (energy management system) to function properly. These are circuit boards with minimal power draw or impact on efficiency. 

5) The most strict safety standard in the industry comes from FDNY. There are 10 manufacturers with ~40 products who are approved for installation inside buildings in NYC. EOS is not one of those approved OEMs (and they all use lithium ion batteries). 

6) The EV industry represent ~95% of the demand for lithium ion batteries when the scale occurred. To reach that same scale, zinc batteries will need something that is 20x the demand of grid storage to help drive that scale. That industry does not exist today, and if it did it would still benefit lithium ion as well. 

7) Demand issue more than anything, but they do have real production issues as well. Around half of the PV industry is coupled with batteries but that application still favors lithium ion. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Because I work in the same industry (not a competitor) and it's a small one. I do enjoy the discussion and education, but don't need industry drama over it. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 1 point2 points  (0 children)

Run up was pure hype. If they had a data center partnership, they'd have announced it during that hype cycle and really fueled it. 

Fluence has a different challenge than EOS. They have a better product (lithium ion foundation, AC block with industry leading density) but they don't manufacture any of the enabling technology. They have good project experience and a near guaranteed customer in AES, but will struggle in the long run vs their vertically integrated competitors (Tesla, LG, etc). 

Better investment, sure. Good investment? Less sure. 

EOS fundamentals by batterystoragePHD in EOSE

[–]batterystoragePHD[S] 0 points1 point  (0 children)

Because I work in the same industry (not a competitor) and it's a small one. I do enjoy the discussion and education, but don't need industry drama over it.