Model-based Design Vanadium Redox Flow Batteries

PDF Publication Title:

Model-based Design Vanadium Redox Flow Batteries ( model-based-design-vanadium-redox-flow-batteries )

Previous Page View | Next Page View | Return to Search List

Text from PDF Page: 070

Section 3.4  Efficiency definitions Faraday’s constant, it can be interpreted as an electric current, as shown in Eq. (3-6) for the negative tank and in Eq. (3-7) for the positive tank. As identical flow rates for each cell are assumed, the flow rate is placed in front of the summation. NC ITIn􏱡 􏰵 FQC 􏱤 c2Ck􏱡 k=1 NC ITIn􏰷 􏰵 FQC 􏱤 c5Ck􏰷 k=1 (3-6) (3-7) By multiplying the equivalent tank current with the open circuit voltage (OCV) of the corresponding tank (positive or negative), the equivalent electrochemical tank power, PT, is computed. It is split into the input tank power, PTIn, shown in Eq. (3-8) and the output tank power, PTout, shown in Eq. (3-9). We can compute the tank output power more easily as there is only one ionic concentration of interest per positive and negative tank. PTIn 􏰵 EOCVT􏱡⋅ITIn􏱡 􏰷 EOCVT􏰷⋅ITIn􏰷 (3-8) PTOut 􏰵 FQT􏰻c2T􏱡⋅EOCVT􏱡 􏰷 c5T􏰷⋅EOCVT􏰷􏱋 (3-9) To derive the OCV of the negative and the positive electrolyte in the tank, the Nernst equation is applied, as shown in Eq. (3-10). In [41], formal half-cell potentials of 0.207 V and 1.182 V are measured for the negative half-cell and positive half-cell, respectively. 􏱳EOCVT􏱡􏱴 􏰵 􏱲0.207 V􏱵 􏰷 GT 􏲋ln􏱶c2T􏱡􏱮c3T􏱡􏱷􏲌 (3-10) EOCVT􏰷 1.182 V F ln􏱶c5T􏰷􏱮c4T􏰷􏱷 The actual electrochemical tank power is the difference between the input and output tank power, as shown in Eq. (3-11). PT 􏰵 |PTIn 􏱡 PTOut| (3-11) System power PSys As mentioned before, this work considers the pump power as the only external source of losses. A positive system power corresponds to the charging operation. Thus, power is taken from the grid. The pump power is always positive and always taken from the grid. Consequently, the sign of the pump power does not change for the discharging operation. PSys 􏰵 EPCSIPCS 􏰷 PPumps (3-12) 62

PDF Image | Model-based Design Vanadium Redox Flow Batteries

PDF Search Title:

Model-based Design Vanadium Redox Flow Batteries

Original File Name Searched:

10-5445IR1000070670.pdf

DIY PDF Search: Google It | Yahoo | Bing

Salgenx Redox Flow Battery Technology: Salt water flow battery technology with low cost and great energy density that can be used for power storage and thermal storage. Let us de-risk your production using our license. Our aqueous flow battery is less cost than Tesla Megapack and available faster. Redox flow battery. No membrane needed like with Vanadium, or Bromine. Salgenx flow battery

CONTACT TEL: 608-238-6001 Email: greg@salgenx.com (Standard Web Page)