Aquion Energy up and coming battery....opinions please

[Sunking]

Hey, the CEOs can decide what's in the future

Not IMHO and history says differently. The Market decides, companies just capitalize on the demands.

You are correct the Market demands a better battery. So far Lithium is winning with a huge lead.

[bcroe]

Bruce I agree with what you say about converters. Equipment can be made to work of a 2:1 voltage range. Not at all uncommon. Now put yourself say inside Joe Blow Battery Inverter Manufacture shoes for a minute. Are you going to spend millions to redesign your equipment to work with a queer battery that is way over priced, and take the chance of going bankrupt pricing yourself out of the market passing those cost onto your customers?

Hey, the CEOs can decide what's in the future, us engineers just tell what works today. Given
our current difficulties with batteries, we should leave no stone unturned. That micro grid
project in HI ought to be a good trial, probably all new equipment. Bruce

[Sunking]

How often is the last 50% used with FLA's? Not very. Almost everyone recommends running the generator if the DOD with FLA's get close to 50% DOD. The same DOD is readily available with Aquion.

No it is not available as that is below 40 volts. No 48 volt equipment can access it. To get the same requires the Aquion to be twice as large. You can take FLA down to 80% DOD if needed. You just canno tlet them stay there or do it often. It is no contest. FLA is better bang for the buck both long and short term.

If the Aquion is so great why do they only warrant them for 24 months A Walmart battery comes with a 24 moth warrant and no hassle claim. A good FLA like Rolls 5000 comes with 7 years at 1/4 the cost and will last longer until proven wrong. Its no contest.

[northerner]

I wouldn't argue with that. Its really not the same issue I was referring to.


What I liked most about Aquion, is the ability to tolerate severe DOD for some time without
damage. Lets recommend them to all those people who would wreck their first battery set.
Bruce Roe

And recommend them to those who are both interested in overall long term savings and minimizing impact on the environment.

[northerner]

Bruce the last 50% of capacity on Aquion battery is not usable once the voltage drops below 40 to 42 volts on a 48 volt system. The Ri of the Aquion battery is so high forces you to significantly over size the battery by 100%. They are completely useless IMHO, and because of that fact they will go bankrupt when the market discovers that fact. I waited 5 years for them to publish specs. What a disappointment. I really feel sorry for their customers.

How often is the last 50% used with FLA's? Not very. Almost everyone recommends running the generator if the DOD with FLA's get close to 50% DOD. The same DOD is readily available with Aquion batteries, and if you size the bank for a normal 20 to 30% daily DOD, there should be no problem with system voltages, providing you don't have extremely heavy loads relative to your overall average load.

I know it would work with my system as my heaviest loads go very occasionally to 2000 or Maybe 3000 watts. Even those loads would pose no problem for an AHI system configured for my needs, where I'm using a daily DOD of 20 to 30 %.

[Sunking]

Bruce I agree with what you say about converters. Equipment can be made to work of a 2:1 voltage range. Not at all uncommon. Now put yourself say inside Joe Blow Battery Inverter Manufacture shoes for a minute. Are you going to spend millions to redesign your equipment to work with a queer battery that is way over priced, and take the chance of going bankrupt pricing yourself out of the market passing those cost onto your customers?

[bcroe]

Battery Voltage Range

Bruce the last 50% of capacity on Aquion battery is not usable once the voltage drops below 40 to 42 volts on a 48 volt system. The Ri of the Aquion battery is so high forces you to significantly over size the battery by 100%. They are completely useless IMHO, and because of that fact they will go bankrupt when the market discovers that fact. I waited 5 years for them to publish specs. What a disappointment. I really feel sorry for their customers.

I wouldn't argue with that. Its really not the same issue I was referring to.

If in fact the regular cell operating range is 1.25V to 2.45V (1.96:1), Aquion batteries are
a very poor substitute plug in to many existing systems. As I recall most recently we were
designing office equipment to nominally run 39.5V to 54V, with a capability to 60V.
Those were disconnect points.

HOWEVER, the capability to use this range has existed for a while. DC - DC converters with
an input of 36V to 72V are common. Plug ins running on rectified AC will accept 120AC to
240 VAC or anything between. My 7.5KW grid tie inverters have an operating input range of
230V to 500V (with tolerance of 600V). This sort of equipment could run nicely over such
a battery range. So I see this as a matter of bringing the right equipment together; easy for
a brand new design, not so good for current apps.

What I liked most about Aquion, is the ability to tolerate severe DOD for some time without
damage. Lets recommend them to all those people who would wreck their first battery set.
Bruce Roe

[Sunking]

By the way, FLA's are also way over sized in order to provide a long life system. Many off grid users use only 20-30% average daily DOD!

That is not over sized. You have to have 2 to 3 days autonomy to CYA for cloudy days. To get the same usable autonomy using Aquion batteries would require twice the AH capacity at 8 times the cost.

A utility is designed by engineers who know what the batteries can and cannot do and thus the equipment is custom designed to work with the queer discharge curves and low C rate of the battery. The issue is two fold; economics and equipment compatibility. Aquion economics and compatibility do not work for consumer solar markets.

[northerner]

Bruce the last 50% of capacity on Aquion battery is not usable once the voltage drops below 40 to 42 volts on a 48 volt system. The Ri of the Aquion battery is so high forces you to significantly over size the battery by 100%. They are completely useless IMHO, and because of that fact they will go bankrupt when the market discovers that fact. I waited 5 years for them to publish specs. What a disappointment. I really feel sorry for their customers.

Time will tell. I'm hoping they do work out and become a viable option for storage. Aquion just agreed to provide 1 mwh of storage to a major micro grid in Hawaii.

http://www.aquionenergy.com/press-room/press-releases/aquion-energy-enters-agreement-major-microgrid-battery-system-deployment

The bottom line is the overall cost of storage, which, if the specs they publish are true, could be the case!And at the same time they are environmentally friendly, which in itself, is a selling feature.

By the way, FLA's are also way over sized in order to provide a long life system. Many off grid users use only 20-30% average daily DOD!

[northerner]

The point most seem to overlook, is doing lesser Depth of Discharge isn't saving much
money on batteries. Rather, you trade a high DOD on replacing fewer batteries more
often, against a lower DOD of a larger battery bank replaced less often. Just to compare,
12,000 cycles of 25% DOD is total energy stored over life of 3000 times batter capacity.
4000 cy times 80% = 3200. 6000 times 50% = 3000, they are all about the same lifetime
energy stored per battery $. Bruce Roe

The reason for the recommended lower DOD is prevent system voltage from dropping too low. Below 50% DOD, the voltage of the system could drop low enough with heavier loads to kick out your inverter. Larger storage will not see as significant a drop, and as you mention, you would not loose life time of the bank, as cycle life stays proportional to average DOD. Also, recharging the bank with solar will be more efficient, as currents during charging are on average higher than those during useage (ie during discharge)

[northerner]

They are too expensive, and their usable voltage range (30V - 59) does not align with off the shelf equipment. Can you get to with that restriction? I don't know.

You are going to use them at 25% DOD? If so, you've got a lot more money than I. And floor space. For me, that could cost $45,000. If 12000 cycles is correct (they advertise 4000 @ 80%, 6000 @ 50%). Maybe long term it works out - too many unknowns and expensive for me.

I agree that they are currently too expensive! Particularly, as a new technology, there is risk that they may not deliver as promised or problems could crop up over time. There is definitely a high up front cost with this product that will keep many potential users away.

The system I have is likely not near the size of yours, so the cost to install with 25% DOD would only be a fraction of that cost. Also, a significant price drop is planned at the end of this year from what I have read. I would expect the price to fall over time, just like any new product or technology that makes it's debut.

[Sunking]

The point most seem to overlook, is doing lesser Depth of Discharge isn't saving much
money on batteries. Rather, you trade a high DOD on replacing fewer batteries more
often, against a lower DOD of a larger battery bank replaced less often. Just to compare,
12,000 cycles of 25% DOD is total energy stored over life of 3000 times batter capacity.
4000 cy times 80% = 3200. 6000 times 50% = 3000, they are all about the same lifetime
energy stored per battery $. Bruce Roe

Bruce the last 50% of capacity on Aquion battery is not usable once the voltage drops below 40 to 42 volts on a 48 volt system. The Ri of the Aquion battery is so high forces you to significantly over size the battery by 100%. They are completely useless IMHO, and because of that fact they will go bankrupt when the market discovers that fact. I waited 5 years for them to publish specs. What a disappointment. I really feel sorry for their customers.

[bcroe]

They are too expensive, and their usable voltage range (30V - 59) does not align with off the shelf equipment. Can you get to with that restriction? I don't know.

You are going to use them at 25% DOD? If so, you've got a lot more money than I. And floor space. For me, that could cost $45,000. If 12000 cycles is correct (they advertise 4000 @ 80%, 6000 @ 50%). Maybe long term it works out - too many unknowns and expensive for me.

The point most seem to overlook, is doing lesser Depth of Discharge isn't saving much
money on batteries. Rather, you trade a high DOD on replacing fewer batteries more
often, against a lower DOD of a larger battery bank replaced less often. Just to compare,
12,000 cycles of 25% DOD is total energy stored over life of 3000 times batter capacity.
4000 cy times 80% = 3200. 6000 times 50% = 3000, they are all about the same lifetime
energy stored per battery $. Bruce Roe

[Living Large]

It sounds like these S20 stacks could work for many people who are off grid. The reality is that they would have to be sized for one's systems needs, much like is needed with any other battery type. If you have enough stacks in place, you can keep current flows down and the overall efficiency will be high(er). As a result you would be able to keep the DOD low as well and would get even more cycle life out of them. I believe they are rated for about 12000 cycles at a 25% DOD, correct me if I'm wrong? And they don't suffer a sudden death as many other batteries do when they do approach their cycle life. I don't know of any other battery that could compete with this? Couple that with no maintenance, cell balancing, electrolyte changes, etc... required!

It would be great to hear AHI users chime in. I realize they have just come out and there's not many in use at this point.

They are too expensive, and their usable voltage range (30V - 59) does not align with off the shelf equipment. Can you get to with that restriction? I don't know.

You are going to use them at 25% DOD? If so, you've got a lot more money than I. And floor space. For me, that could cost $45,000. If 12000 cycles is correct (they advertise 4000 @ 80%, 6000 @ 50%). Maybe long term it works out - too many unknowns and expensive for me.

[northerner]

Aquion Batteries

It sounds like these S20 stacks could work for many people who are off grid. The reality is that they would have to be sized for one's systems needs, much like is needed with any other battery type. If you have enough stacks in place, you can keep current flows down and the overall efficiency will be high(er). As a result you would be able to keep the DOD low as well and would get even more cycle life out of them. I believe they are rated for about 12000 cycles at a 25% DOD, correct me if I'm wrong? And they don't suffer a sudden death as many other batteries do when they do approach their cycle life. I don't know of any other battery that could compete with this? Couple that with no maintenance, cell balancing, electrolyte changes, etc... required!

It would be great to hear AHI users chime in. I realize they have just come out and there's not many in use at this point.