Anyone know anything about RedFlow batteries

[solar pete]

Hi All,

I have been asked by a friend/customer to look into using RedFlow batteries for a hybrid install on his house. I have had a quick read about them but I thought I might throw it to the forum to see if any one has any experience or views on the battery they are selling, here is the link, http://redflow.com/products/zbm/

Cheers All

[inetdog]

A quick Google search turned up a couple of Sandia Labs papers, including this one http://www.sandia.gov/ess/publicatio...D2000-0893.pdf

It seems a little early in the technology to introduce this into a residential system unless you have a rabid early adopter willing to take a chance on unknown posssible problems. The Redflow has a 10 year warranty but ZBR has nowhere near ten years of practical experience.

[solar pete]

A quick Google search turned up a couple of Sandia Labs papers, including this one http://www.sandia.gov/ess/publicatio...D2000-0893.pdf

It seems a little early in the technology to introduce this into a residential system unless you have a rabid early adopter willing to take a chance on unknown posssible problems. The Redflow has a 10 year warranty but ZBR has nowhere near ten years of practical experience.

Thanks inetdog, yeh we have a rabid early adopter on our hands here , I have tried to steer them in another direction but they are keen to see if their batteries are possible to use in their situation. I think the deal breaker will be that I cant get access to pricing, I email them today and no reply, no one else I know in solar here have a clue about them, cheers.

While I'm here we are about to have Skype meeting with a vBulletin expert about getting a few things done on the forum, cheers.

[Sunking]

Never used that brand, but familiar Primus Power in the USA.

They are not exactly batteries in the common sense of a chemical reaction. They are basically electroplating machines.

On the plus side

Can be fully 100% discharged with no ill effects and have a cycle life roughly equal to a good quality FLA battery of around 2000 to 3000 cycles.
Non Toxic

On the down side:

Very high $/wh cost of about 300% higher than FLA of roughly $50 to 60-cents per wh
Low Specific Power meaning they cannot be charged fast or discharged fast. This can be a deal breaker for solar because solar requires fast charging. Expressed as Watts/Kg
Low Power Density W/Liter meaning they will need a lot more space for a given capacity.
Cell voltage of 1.8 volts.
Low charge efficiency of 75% which means you will need more panel wattage.

Due to the expense they do not compete with either Pb or Lithium. Either Pb or Lithium out perform them at much lower cost. That is why very few people have ever heard of them.

[solar pete]

Never used that brand, but familiar Primus Power in the USA.

They are not exactly batteries in the common sense of a chemical reaction. They are basically electroplating machines.

On the plus side

Can be fully 100% discharged with no ill effects and have a cycle life roughly equal to a good quality FLA battery of around 2000 to 3000 cycles.
Non Toxic

On the down side:

Very high $/wh cost of about 300% higher than FLA of roughly $50 to 60-cents per wh
Low Specific Power meaning they cannot be charged fast or discharged fast. This can be a deal breaker for solar because solar requires fast charging. Expressed as Watts/Kg
Low Power Density W/Liter meaning they will need a lot more space for a given capacity.
Cell voltage of 1.8 volts.
Low charge efficiency of 75% which means you will need more panel wattage.

Due to the expense they do not compete with either Pb or Lithium. Either Pb or Lithium out perform them at much lower cost. That is why very few people have ever heard of them.

Thanks for chiming in SK, I thought they were going to be expensive, if or when I get some pricing I will lets ya'all know cheers, gota go talk to a man about a solar forum

[inetdog]

SK, their ad blurb talks about them as being ideal for remote communications installations, etc. Since you design(ed?) those for a living I imagine you take issue with that recommendation? Or are they just inappropriate for homeowner use?

[SunEagle]

I would say that each and every energy storage system would have to be judged by the specific "need".

People will pay more to support a "critical" need as opposed to someone just reducing their $200 electric bill by 50%.

[Sunking]

SK, their ad blurb talks about them as being ideal for remote communications installations, etc. Since you design(ed?) those for a living I imagine you take issue with that recommendation? Or are they just inappropriate for homeowner use?

I have looked at them before for remote installations. It has been a few years. At that time the expense was closer to $1/wh compared to $0.18/wh for FLA. Even today you really could not justify the cost. For a remote site you use 10-day autonomy with on site generators so 100% discharge does not gain you anything.

As for Joe Homeowner use the deal breaker is Specific Power is to low to use solar as the charge source. Just like most Gel batteries they cannot be charged fast. Unlike Gel they cannot be discharged fast either. Just like Aquion Batteries if you load them down to more than C/20, the voltage falls off the cliff. Only way to over come that is by Over Size them using a very expensive battery.

Bottom line if you can afford them, you would be better off using Lithium as both are perfect for PSOC operations. Difference is Lithium just has a lot better operating characteristics for same or cost. Not something I would recommend for commercial or consumer use.

EDIT NOTE:

The other characteristic is Cell Voltage (1.8) and Charge/Discharge Curves are incompatible with equipment.

[solar pete]

Thanks for chiming in peeps.

This is what I got back from my enquiry, short version is they are bringing something out suitable for use in PV applications around March.

From Redflow

Thank you for your enquiry and interest in the Redflow home energy storage product. While we already sell our ZBM battery module itself for other applications, we are still in the process of developing a packaged, “easy to use and install” solution for the residential market. We will be releasing full details about our home energy storage battery towards the end of March. At this time we will be releasing an online product information pack, which includes:

· Product features
· Product price guidance
· Battery storage size
· Compatibility with existing inverters
· How to order an energy storage system using our battery

As your question relates to the above, we will contact you at the end of March and provide these details then. So that we can do this easily, would I be able to add your details to our residential emailing list? System deliveries for Australian customers are expected to occur from mid-2016. I am unsure if that will fit with your and your customer’s timeline but hope that it might.

The system will include a battery inverter (made by Victron) and the ZBM already includes a battery management system. If you have any other questions, please do not hesitate to email me back directly.

[inetdog]

I would instead say that they are bringing out a system targeted at the home market. It is hard to see how they can manage suitable.

[Sunking]

Pete I read between the lines. Meaning our sales are so poor we are trying to find and create another market to save our ass.

[solar pete]

Howdy Guys so it looks like the thing to take away is that the chemistry of these batteries does not lend itself to being used in a system where PV is the main re-charge source as it doesn't like to be charged to quickly. I get it, cheers