Storage
Template
General description of storage technology. I.e. the first two lines of related Wikipedia article.
Materials
- Cathode:
- Anode:
- Electrolyte:
- Other:
Efficiency
- Storing: xx%
- Feeding back: xx% gets less efficient with high power output
- Overall: xx%
Other features
- DoD: xx%. This is an arbitrary value, because off-course all cells can be discharged till 100%. However, most batteries have decreasing lifetimes with lower DoD.
- Cycles: # @xx%DoD (# cycles until 80% of initial capacity is left)
- Lifetime (@1000 Cycles @DoD80%): x Yr
- Lifetime (either limited by float lifetime or use @365 cycles /Yr 33%DoD: x Yr
- Energy density: xx Wh/kg
- Price: xx €/kWh
- Stage of development:
- Other:
Sustainability
- Recycleable?
- Toxicity?
- Production energy input?
- Resource aspects?
Companies
- Potential partner x
- Potential partner y
Hydrogen / Seasonal storage
Only technology that is truly capable of seasonal energy storage, according to OECD-IEA Energy Technology Perspectives 2014
Efficiency
- Best practice electrolysis efficiency: 50 to 80%
- Fuel cell efficiency: (Nedstack PEM fuel cell): 50% electrical energy, with 40% waste heat (which can theoretically be used as well) Net theoretical efficiency: 25-40%, with an additional 20-32% reusable waste heat.
Companies
- SFC (Germany), methanol (NOT H2)
- Nedstack PEM fuel cells (NL)
- Arcola (UK)
- Electro Power Systems - their product is called the Electro Self, ranging from 1.5 - 12 kW output, with a 5.5kW electrolyzer.
- FutureE - A German company that also makes a similar system
- Acta Power - they also have a hybrid system that uses their own electrolyzer tech, but the fuel cells come from FutureE. The two companies target different markets to avoid direct competition.
Products
PDF Overview of fuel cell technology by FuelCellToday
Mid-term storage
(most technical parameters about battery types are cited from Rydh, C. J. & Sandén, B.B. (2005). Energy analysis of batteries in photovoltaic system. Part I & II. Energy Conversion and Management . 46.). Commercial datasheets usually provide more optimistic values, probably (this is an assumption) because those values are under ideal circumstances (temperature, load/charge user charactaristics etc. This paper may also be consulted if some parameters may be unclear).
LiFePo4
Lead acid
Lead acid batteries are the most commenly used batteries. They can deliver a lot of instant power, but are heavy, efficiencies are relatively low, the lifetime is not very long, especially when the batteries are discharged to deep and when no full charge-discharge cycles are performed (which is not the case in a household tipically). The biggest advantage is, that they are CHEAP. However, the lower lifetime and efficiency result in a worse cost-efficiency then you would think on first sight. Lead is of f course toxic, but the advantage of lead acid batteries being mainstream, is that there is infrastructure for recycling those batteries.
Within lead acid batteries, there are mainly three types. Below those are described with some characteristics. Wet cells (Electrolyte is fluid): High DoD, higher O&M to prevent dry-out, relatively short lifetime, lot of H2 production Gel (electrolyte is suspended in sylica type gel): Long lifetime, lower DoD, AGM (electrolyte is absorbed in a glass matt structure); Similar to Gel, but a bit shorter lifetime, however able to deliver higher peak output (due to lower internal resistance).
Materials:
- Cathode: Pb + HSO4– → PbSO4 + H+ + 2e–
- Anode: bO2 + 3H+ + HSO4– + 2e– → PbSO4 + 2H2O
- Electrolite: H2SO4
Efficiency
- Storing: xx% typically af low as 80% or less in last 80% of charge cycle
- Feeding back: xx%
- Overall: 70-84%
Other features
- Max DoD: 20-50% (Wet cells-AGM/Gel)
- Cycles: 400-1000 @80%DoD
- Lifetime (@1000 Cycles @DoD80%): 3-4 Yr
- Lifetime (either limited by float lifetime or use @365 cycles /Yr 33%DoD: 15-20 Yr
- Energy density: 15-20 Wh/kg
- Price: 1 €/kWh
Sustainability
- Recycleable?
- Toxicity?
- Production energy input?
- Resource aspects?
Companies
- American Vanadium (cellcube)
- Potential partner y
Redox Flow batteries
(energy content is not limited by surface area):
Vanadium Batteries
The vanadium redox (and redox flow) battery (VRB) is a type of rechargeable flow battery that employs vanadium ions in different oxidation states to store chemical potential energy.[2] The vanadium redox battery exploits the ability of vanadium to exist in solution in four different oxidation states, and uses this property to make a battery that has just one electroactive element instead of two.
Materials:
- Cathode: In solution: V2+ <> V3+
- Anode: In solution: V4+ <> V5+
- Electrolyte: –
Efficiency
- Storing: xx%
- Feeding back: xx%
- Overall: 60-80%
Other features
- Max DoD: xx%
- Cycles: # @xx%DoD
- Lifetime (@1000 Cycles @DoD80%): 3-4 Yr
- Lifetime (either limited by float lifetime or use @365 cycles /Yr 33%DoD: 15-20 Yr
- Energy density: 15-20 Wh/kg
- Price: xx €/kWh
Sustainability
- Recycleable?
- Toxicity?
- Production energy input?
- Resource aspects?
Companies
- American Vanadium (cellcube)
- Potential partner y
Hybrid Flow batteries
(Two electrodes, energy content is limited by surface area):
Hybrid Manganese Batteries
Materials:
- Cathode; Manganese Oxide
- Anode: Carbon Composite
- Electrolyte: Sodium Sulfate
- Other: Synthetic Cotton Separator
Efficiency
- Storing: xx%
- Feeding back: xx%
- Overall: ~80% (scientific report) 90% (aquion supplier)
Other features
- DoD: 100%
- Cycles: # @xx%DoD
- Lifetime (@1000 Cycles @DoD80%): x Yr
- Lifetime (either limited by float lifetime or use @365 cycles /Yr 33%DoD: x Yr
- Energy density: xx Wh/kg
- Price: <300 $/kWh
- Stage of development: large scale demo projects realized, for sale
Sustainability
- Recycleable?
- Toxicity?
- Production energy input?
- Resource aspects?
Companies
- Hybrid aquious hybrid ion: Aquion Energy
Hybrid Ion “seasalt” batteries
Molten salt batteries (including liquid metal batteries) are a class of battery that uses molten salts as an electrolyte and offers both a highenergy density and a high power density.
Materials:
- Cathode;
- Anode:
- Electrolyte:
- Other:
Efficiency
- Storing: xx%
- Feeding back: xx%
- Overall: ~90%
Other features
- DoD: 90%
- Cycles: 7000 @xx%DoD
- Lifetime (@1000 Cycles @DoD80%): x Yr
- Lifetime (either limited by float lifetime or use @365 cycles /Yr 33%DoD: x Yr
- Energy density: 30-40 Wh/kg
- Price: towards 100 €/kWh
- Stage of development: Possible to buy more expensive demo packs, based in NL
- Other: High working temperature
Sustainability
- Recycleable?
- Toxicity?
- Production energy input?
- Resource aspects?
Companies
- Dr. Ten
- Potential partner y
- Aquion (the only cradle2cradle certified battery) M100-LS83 M100-L083 Prelim Tech Info Sheet.pdf