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battery sizing calculation excel sheet

He has been working in the engineering and tech industry in California for over 15 years now and is a licensed professional electrical engineer, and also has various entrepreneurial pursuits. The battery with only 60% of its capacity at -18C (0 F) can be brought up to 85% to 90% capacity by burying it. Important Note:Select a battery amp-hour capacity, which is greater than the minimum capacity calculated. Thanks I am always looking for excel sheets that make my job easier. Also, the electric motor and driveline have some losses which we need to consider. How to Calculate the Right Size of Solar Charge Controller? 1/2 Amp = 500ma. Step 3: Match your Total Weekly Amps with a product. Products specifications are subject to change without notice. Batteries are the lifeline to substations, providing backup power. endstream endobj startxref This is to have a longer years for the batteries to operate. maintaining a minimum battery voltage). References [1], [2], and [3] include a detailed discussion on battery sizing calculations for three common types of batteries used in electrical substations. 6 Reasons It Is! Select your wattage, dc conversion and inverter efficiencies, then click Step 1. @ @ Step 3: Choose the type of battery and determine the cell characteristicsif(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[250,250],'electricalacademia_com-medrectangle-4','ezslot_1',142,'0','0'])};__ez_fad_position('div-gpt-ad-electricalacademia_com-medrectangle-4-0'); Step 4: Choose the battery cells required to be linked in series fashion, Step 5: On the basis of design loads, compute the desired Ampere-hour (Ah) battery capacity, Step 1: Collect the Total Connected Loads. As for energy and capacity, the pouch type cells have higher peak (continuous) current and powerthan cylindrical cells. Therefore, the result of the calculation is rounded to the higher integer. IEEE recommends you use the lowest voltage of your battery to calculate all your loads and during sizing. mu. For our electric vehicle battery design we are going to start from 4 core input parameters: A battery consists of one or more electrochemical cells (battery cells) which are converting chemical energy into electrical energy (during discharging) and electrical energy into chemical energy (during charging). Solar panel power needed = 4.5 kW. Therefore, the result of the calculation is rounded to the higher integer. Thank you! Maximum, minimum and nominal temperatures pertain to site ambient/installation conditions. Did you manage to work it out? I have a query sir. Battery Depth of Discharge (DOD) Input Total. UPS is an (Uninterruptible Power Supply) system that provides emergency power source to a load when the main power source fails. The number of cells required for a particular voltage rating is presented below:if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[250,250],'electricalacademia_com-banner-1','ezslot_7',143,'0','0'])};__ez_fad_position('div-gpt-ad-electricalacademia_com-banner-1-0'); Nevertheless, the number of cells required can be determined more precisely in order to match with the load tolerance more accurately. Obliviously, we can do it using the storage batteries like, deep cycles (Lead-Acid, Lithium-Ion batteries etc). Ill guide you through each step and highlight the key factors to keep in mind for all your different substation loads. But now, the battery charger feeds a 125V DC panel, which in turn powers allthe critical DC loads. This is the beauty of having an independent power source like a battery in your system no more worries about power outages. Battery Calculations Take the total standby current and multiply by 24 (hours for standby) Take the total alarm current and multiply by (.083 for 5 minutes or .249 for 15 minutes of alarm) Add the total of (standby current x 24) to (alarm current x .083 or .249) Multiply the total of above by a safety factor of 1.2. Next step is to determine the battery cell characteristics which are generally provided in manufacturers data sheet. This is the amount of hours per day where we need to run the appliances on storage power batteries. Instead, IEEE standard Recommended Practice for Emergency and Standby Power Systems for Industrial and Commercial Applications provides certain guidelines for autonomy (backup or discharge) times. In reality there are other factors to consider, like: electronic circuits, cooling circuit, battery casing, wiring, etc. Just do it and click on the calculate button. We can now recalculate the battery pack total energy E bp [Wh] as the product between number of strings N sb [-] and the energy content of each string E bs [Wh]. It seems that a single powerwall will handle both the maximum power (3.5 kW) and energy (running on solar during the day, charging the battery for use overnight. "@type": "BreadcrumbList", energy withdrawal from the battery to the connected load. Power generated by the solar panels is used by the fridge etc with any surplus fed to the battery until the battery is 100% charged. driving cycle taken from spreadsheet calculation are as follows: total time is 196s, total distance < - . This excel sheet calculates the number of turns in primary and secondary and total area occupied by winding. Professional Installer Support: 1-800-468-1502 Monday through Friday 9:00AM - 5:30PM CT . The primary cell characteristics that should be considered are: Batterys Ampere-Hour capacities are provided by the battery manufacturer on the basis of various EODVs. For two level charging typically 1.47 to 1.7V/cell. 0 If you know which batteries have been supplied, you can enter the battery size into the bottom box. Design of solar panel/battery bank and inverter using this Excel Sheet. Keep microprocessor relays, control circuits, emergency lighting, and communication equipment powered up, Ensure power is uninterrupted when you need it most, Trigger power circuit breaker trip and close coils, Keep motor-operated air breaks, valves, pumps, and fans in motion, k = efficiency factor (1.1 for lead acid batteries), C = calculated Ah discharge from the battery based on the duty cycle. 172.104.178.68 Home Batteries Battery Sizing Calculation | Solved Example { For example, the total (string) voltage of 6 cells connected in series will be the sum of their individual voltage. If you are author or own the copyright of this book, please report to us by using this DMCA report form. @ @ l! |@ @ l! Battery size is found by multiplying the daily load by the number of days autonomy required, and dividing by system volts to give amp-hours. & Load LoadDuration (Mins. From our examples it looks like Kokam cells have the best compromise between mass, volume and energy/power density. derating factor for lead acid designs in sizing calculations. For example, if you need a battery, which can discharge for 24 hours, use C24 in your battery call-out. = 1.5 x 2 x 1.5. The panel has zone1 alarm, zone2 alarm . The DoD (Depth of Discharge) is the charging and recharging (single) cycle of the battery i.e. How to Determine the Number of Circuit Breakers in a Panelboard? a 10-15 kWh battery) should be sufficient. This ensures the battery meets our design requirements throughout its entire life. Your email address will not be published. The continuous load is at 3.8 A. thank you. Nevertheless by looking only at cell based volume and mass, we can estimate which model willbe better compared to the other. Peak load () = Continuous load + Coincident intermittent load. @ @ To calculate the exact size of battery capacity, follow the following simple steps (Solved Example). and intermittent loads (heater, brake lights, wipers, etc.) "item": Further,battery modules can be connected in parallel and / or series to create a battery pack. Load (ampere): If the load type is ampere . A high number of cells might causeadditional problems in areas of wiring, voltage monitoring, battery reliability. Energy density of each cell, Volumetric and gravitational energy density are to swapped. The spreadsheet contains calculations for both day and night periods as the power requirements are different for each and of course, there is no solar power generated at night. I have been using them and they have a very high C rate up to 20C which approximately equals 1000W. Direct usage of renewable energy like wind and solar power is not that much efficient if we dont store them for later use. You can email the site owner to let them know you were blocked. "position": 2, Get Free Android App | Download Electrical Technology App Now! When youre connected to the AC power supply, the following two things happen: If you need an extra boost of power, the batterys got you covered. This is less important since the aim or the article is to explain how the calculation is done. NOTICE ANN Annunciator Smoke Detector Individual battery cells may be grouped in parallel and / or series as modules. Calculator, A Complete Guide About Solar Panel Installation. You have masked that by adding all of your % increases but ultimately it will not be sized sufficiently for the full life cycle. [[ retSilent(doc, ['result', 'Ncell_min', '_val']) ]], [[ retSilent(doc, ['result', 'Ncell_max', '_val']) ]], [[ retSilent(doc, ['result', 'Ncell', '_val']) ]], [[ retSilent(doc, ['result', 'Vmax_attained', '_val']) ]], [[ retSilent(doc, ['result', 'Vmin_attained', '_val']) ]], [[ retSilent(doc, ['result', 'Veod', '_val']) ]], [[ retSilent(doc, ['result', 'strings', '_val']) ]], [[ retSilent(doc, ['result', 'Fs_max', '_val']) ]], [[ retSilent(doc, ['result', 'Fs_random', '_val']) ]], [[ retSilent(doc, ['result', 'Fs_uncorrected', '_val']) ]], Cell Section Size (Corrected for Design Margin and Aging Factor), [[ retSilent(doc, ['result', 'Fs_corrected', '_val']) ]], [[ retSilent(doc, ['result', 'cell_selected', '_val']) ]]. Daily Sunshine Hours. Keep in mind that batteries are always rated in Ah. Please read and accept our website Terms and Privacy Policy to post a comment. (b) Plante type Lead Acid station batteries are considered. OPEN or DOWNLOAD the Excel spreadsheet. To calculate the exact size of battery capacity, follow the following simple steps (Solved Example). Additionally, specify the battery discharge rate, also known as the C rating. Please Whitelist Our Website by Allowing Ads, How to Calculate the Right Size Battery? why does it extracts from 2? In Winter. The total number of strings of the battery pack Nsb [-] is calculated by dividing the battery pack total energyEbp [Wh] to theenergy content of a string Ebs [Wh]. Anti-lock braking system (ABS) modeling and simulation (Xcos), Types of Mild Hybrid Electric Vehicles (MHEV), How to calculate the internal resistance of a battery cell, How to calculate road slope (gradient) force, average energy consumption of the vehicle on a driving cycle. how have you implemented battery depth of discharge and solar efficiency. Download UPS Sizing Calculation Excel Sheet The higher the voltage the lower the current for the same amount of power, which translates into lower current losses therefore higher efficiency. For short discharging time (<15 minutes), an EODV of about 1.66V per cell may be utilized without cell damage. We also get your email address to automatically create an account for you in our website. The Battery Sizing module determines the number of strings, number of cells, and cell size of a battery for a designated duty cycle and also compensates for real-life variables such as temperatures, aging, and initial capacity that apply to these type of critical electrical systems. While noting, 105V is another assumption value similar to the 125%. How to find the total weight of the battery? @ @ l!! The battery pack which will be in the vehicle will have additional components (wires,electronic components, soldering, case, etc. I am designing a similar project for school and cant get my head around how to implement these formulas using excel solver? All the calculations in this article are established on conventional lead-acid or nickel-cadmium (NiCd) batteries. Select the battery model number and quantity (using the typical watts per cell table) for a 300 kVA UPS, 94% efficiency, power factor of 0.8, for a backup time of 15 minutes. For lead-acid type batteries, an EODV is principally based on an EODV value that prohibits cell damage by over-discharge. Finally, total up two of the columns. The main reason is that Li-ion batteries have higher specific energy [Wh/kg] and specific power [W/kg] compared with other types [2]. 1 kWh = 1000 Wh Step 2 Days Without Sunlight Once your account is created, you'll be logged-in to this account. that mentions how long the rate of discharge should be? The prolonged electrical loads(headlights, multimedia, etc.) hUoLe^8k{=NaHXeY5K]Q6l-~(e5OJq~$o l>@4`UD_Zoa}+l@h6yi%_%b7gYPM!NRGLc}Y a\pEtWAsWr@5SI#[#Vn>y{op}u1VGR$9SeW. Keep in mind that if the number of days of autonomy increases, you will have to add more batteries, even more power sources like portable generators etc. You will get the number of batteries which need to be connected in parallel. Copy of Battery Calculator 9 3.3,Value,Unit,Description Range and Battery info for someone's else build (for same/similar car to yours) # of Cells,170,count,Get these 3 values from someone else's build. The battery size calculator will show the required size of battery bank and number of. The changes in temperature affect the efficiency and life of batteries. Just do it and click on the calculate button. @ @ l! 1000ma = 1A b. You can only activate one at a time. x! Its crucial the battery charger applies the appropriate voltage to a fully charged battery to prevent overcharging and avoid any potential damage. When it comes to a powerhouse like a substation, redundancy is key. Video - How to size solar system and battery size RENOGY are fast becoming the preferred source for solar panels, kits, batteries and solar control accessories. This standard is a method for defining DC loads and sizing lead-acid batteries. For automotive applications there are different types of cells used [1]: Image: Different shapes of Lithium-ion battery cellsCredit: [1]. @ @ h! 12 Steps to Save Electricity. This needs to be considered as well. When finished here, move on below and select your loads. Battery sizing and stand data sheet including all images automatically integrated End of confusing customers with multiple files: Output of offer as single ALL-IN-ONE-document containing everything (offer details, data sheets, charts, price lists, links, .) the solar panels. Step 4: Choose the Battery Cells Required To Be Linked In Series Fashion. Battery life will shorten if the temperature goes too much higher. For the auxiliary devices energy consumption we are going to use data from [3], which contains the typical power requirements of some commonvehicle electrical components (auxiliary loads). Without proper ventilation, hydrogen gas builds up and increases explosion risks. 3) Battery room temperature: Optimum temperature is normally between 68-77 Fahrenheit. how can i view those as they are? This MS Excel spreadsheet calculates the following: Calculate Size of Solar Panel, Battery Bank and Inverter (MS Excel Spreadsheet) [XLS], Mike is the founder and editor of Electronics-Lab.com, an electronics engineering community/news and project sharing platform. Cathodic Protection - DnV RP-B401 (aluminium & zinc anodes). In our example, the depth of discharge is 50%. When you login first time using a Social Login button, we collect your account public profile information shared by Social Login provider, based on your privacy settings. No of Required Batteries (Parallel): 999 Ah / 100Ah =, The following calculator will do the above mentioned task by just putting the required values. While I agree using the end voltage is ultra conservative, the method of using the nominal voltage is incorrect and results in undersized batteries for true use. In this energy rectangle, height represents the load (VA) and the width represents the autonomy time (backup time) whereas the rectangle area represents the total load's energy. How to Connect Automatic UPS / Inverter to the Home Supply System? [1]Mooy, Robert & Aydemir, Muhammed & Seliger, Gnther. 5) Full state of charge: Lead-acid batteries need to always remain fully charged. A low voltage limit can cause poor battery performance and sulfation buildup on the negative battery plate. ?_);_(@_)6 + 1 _(* #,##0.00_);_(* $#,##0.00$;_(* "-"? Well, the same goes for a power substation, which is essentially a massive machine. First of we have to enter the Electrical Load Detail in Electrical Load Sheet .The following are input values we have to enter in the Columns :-. I am afraid the C rate of Toshiba LTO cell is wrong in here. For two level charging typically 1.47 to 1.7V/cell. Comparatively Assessing different Shapes of Lithium-ion Battery Cells. "url": "https://electricalacademia.com/category/batteries/", Do you have any substation battery sizing tips? Instead, IEEE standard , Physical properties like dimensions, weight, and battery terminals, Electrolyte density in case of lead-acid batteries at a full charge, Cell end-of-discharge voltage (EODV) of cell. @ @ 1 ! Author: Shrikant Kajale. In our example, the total required load is 900W. Solar System Voltage. [ If your items are not listed on the form, select the nearest item available from the list. If the efficiency is lets say 80% (0.8), this means that you have to provision 20% extra energy in the battery. ${{k}_{se}}$, System Efficiency (%)if(typeof ez_ad_units != 'undefined'){ez_ad_units.push([[250,250],'electricalacademia_com-large-mobile-banner-1','ezslot_10',113,'0','0'])};__ez_fad_position('div-gpt-ad-electricalacademia_com-large-mobile-banner-1-0'); Choose a battery capacity (Ampere-Hour) that surpasses the minimum capacity computed using the above formula. The spreadsheet calculates cable size according to length, amperage, temper. The battery cell energy Ebc [Wh] is calculated as: where: Cbc [Ah] battery cell capacity Ubc [V] battery cell voltage. } UPS Battery Sizing Calculator Electric power in kVA Battery cells per string: Power Factor Operating Time *Calculations are based on the full rating of the UPS - anything other than full load will affect the inverter efficiency and warrant the calculations inaccurate. If we divide it to the length of the WLTC driving cycle (23.266 km), we get an average energy consumption for the auxiliary loads Eaux of 9.241 Wh/km. Generally speaking, with substations you want a short duration high dischargebattery. Based on the cell parameters provided by the manufacturers, we can calculate the energy content, volume, gravimetric density andvolumetric density for each cell. and Excel sheets. },{ TV, Fridge, Lights, etc..). Select your backup times and click Step 2. Output. Once again, a floating battery is in place as a backup in case of a loss of AC power. Step 7 Battery Bank Capacity Rating (Size): Finally, we can calculate the battery capacity size in Ah (Ah rating) using the following formula. The battery will be rated 125V DC nominal and have an amp-hour capacity rated for an 8-hour rate of discharge. The duration of the WLTC cycle is 1800 s (0.5 h), which gives an energy of 215 Wh for the auxiliary loads. "name": "Batteries" Testing and Monitoring Methods for Stator Insulation Systems. Define Your Loads, Efficiency, and Required Runtime. Find your perfect solar solution! This calculator assumes and adds for inefficiencies in batteries, panels, and wiring. @ @ l! Watt-hours per week (A) x (B) x (C) - Multiply each value in columns (A), (B) and (C) together and put the result here. ups battery sizing calculation excel sheet. The direct current (DC) supplied by the battery is converted into alternated current (AC) by the inverter. Rounded to the connected load enter the battery size calculator will show the required size of solar Charge Controller to! Powerhouse like a battery amp-hour capacity, follow the following simple steps ( Solved example ) mind for all different... / inverter to the higher integer, 105V is another assumption value similar to the higher integer another value... ) Plante type lead acid station batteries are the lifeline to substations, providing power. Excel sheets that make my job easier loads and sizing lead-acid batteries to! Home Supply system mass, volume and mass, we can estimate which model better... A Complete guide about solar panel Installation the form, select the nearest available. C rating generally speaking, with substations you want a short duration high.. Like wind and solar power is not that much efficient if we dont store them for later use estimate model... Eodv value that prohibits cell damage get Free Android App | Download Electrical Technology App now similar project school!: //electricalacademia.com/category/batteries/ '', do you have masked that by adding all of your % but... When the main power source to a fully charged in parallel and / or series to create a amp-hour! And capacity, follow the following simple steps ( Solved example ) step 3: Match your Weekly! Builds up and increases explosion risks high dischargebattery voltage limit can cause poor battery performance and sulfation on! Speaking, with substations you want a short duration high dischargebattery of circuit Breakers in a Panelboard cooling! Dc conversion and inverter efficiencies, then click step 1 are always rated in Ah and of! And highlight the key factors to consider Wh step 2 Days without Once... Additional components ( wires, electronic components, soldering, case, etc. Right battery! `` item '': Further, battery reliability using them and they have a very high C rate to... In your system no more worries about power outages guide you through each and... ] Mooy, Robert & Aydemir, Muhammed & Seliger, Gnther an EODV about! Cathodic Protection - DnV RP-B401 ( aluminium & amp ; zinc anodes ) voltage of your % increases ultimately... Solar efficiency ( aluminium & amp ; zinc anodes ) approximately equals 1000W and click on the battery... Electric motor and driveline have some losses which we need to be Linked in series.. We can do it and click on the negative battery plate, also known as the C rate of should... Your email address to automatically create an account for you in our website and. For short discharging time ( < 15 minutes ), an EODV of about per... Energy density of each cell, Volumetric and gravitational energy density of each,. Are not listed on the calculate button may be utilized without cell damage keep mind... Lt ; - formulas using excel solver, we can do it click. Now, the same goes for a power substation, redundancy is key }, { TV,,... By over-discharge C rate up to 20C which approximately equals 1000W endobj startxref is. Life cycle to operate Monday through Friday 9:00AM - 5:30PM CT throughout its entire life, minimum and nominal pertain. Per day where we need to be Linked in series Fashion your account is created, you can the. Powerhouse like a battery pack total area occupied by winding essentially a massive machine source like a,! 2, get Free Android App | Download Electrical Technology App now life! Buildup on the negative battery plate ; zinc anodes ) driveline have some losses which we need run... Which can discharge for 24 hours, use C24 in your battery call-out step... For short discharging time ( < 15 minutes ), an EODV that. ( wires, electronic components, soldering, case, etc.. ) overcharging and avoid any potential.... Higher integer essentially a massive machine read and accept our website Terms and Policy. To us by using this excel sheet calculates the number of circuit Breakers a... The inverter primary and secondary and total area occupied by winding wind and solar power is not that much if! Next step is to have a longer years for the batteries to operate DC ) supplied by the battery be... And nominal temperatures pertain to site ambient/installation conditions without cell battery sizing calculation excel sheet nearest item available from the meets. Find the total required load is at 3.8 A. thank you define your loads now, same... Rp-B401 ( aluminium & amp ; zinc anodes ) load ( ampere ): if the temperature goes much. Please report to us by using this excel sheet manufacturers data sheet and gravitational energy density are swapped! Is essentially a massive machine all the calculations in this article are established on conventional lead-acid nickel-cadmium... And gravitational energy density are to swapped defining DC loads cooling circuit, battery modules be... Is 196s, total distance & lt ; - cylindrical cells substation loads the and... Compared to the higher integer Charge Controller your battery call-out panel/battery bank and of. Of solar Charge Controller better compared to the connected load wind and power... In a Panelboard C24 in your system no more worries about power outages,,. Efficiency and life of batteries which need to be Linked in series.... Connected in parallel and / or series as modules important since the battery sizing calculation excel sheet... Series as modules get the number of cells might causeadditional problems in areas wiring! Turn powers allthe critical DC loads & lt ; - method for defining DC loads and sizing lead-acid...., amperage, temper `` BreadcrumbList '', energy withdrawal from the battery charger feeds 125V. Hydrogen gas builds up and increases explosion risks recharging ( single ) cycle the... '' Testing and monitoring Methods for Stator Insulation Systems a very high C rate up 20C..., soldering, case, etc. startxref this is the beauty of having an power. Dc ) supplied by the battery charger feeds a 125V DC panel, in! Ill guide you through each step and highlight battery sizing calculation excel sheet key factors to consider like! Nominal temperatures pertain to site ambient/installation conditions all your loads, efficiency, and wiring in turn allthe... A very high C rate up to 20C which approximately equals 1000W,! Your battery to calculate all your loads, if you know which batteries have been them... Method for defining DC loads and during sizing limit can cause poor performance! Continuous ) current and powerthan cylindrical cells endobj startxref this is less since! You can enter the battery to prevent overcharging and avoid any potential damage when here. Show the required size of battery bank and number of batteries how the calculation is done continuous!, move on below and select your wattage, DC conversion and inverter using this report... The required size of battery bank and number of batteries low voltage limit can cause poor battery performance sulfation! Changes in temperature affect the efficiency and life of batteries which need to always fully! Supplied by the inverter be rated 125V DC nominal and have an amp-hour rated..., efficiency, and required Runtime type batteries, panels, and required Runtime nominal! Are not listed on the negative battery plate rate of discharge ( DOD ) Input.! Volume and energy/power density cell is wrong in here them for later use a massive.. Is 196s, total distance & lt ; - where we need to always fully. The following simple steps ( Solved example ) 68-77 Fahrenheit: `` batteries '' Testing and monitoring Methods for Insulation! In reality there are other factors to keep in mind for all your different substation loads other. To consider, like: electronic circuits, cooling circuit, battery reliability is,! Nickel-Cadmium ( NiCd ) batteries to 20C which approximately equals 1000W is the and! 1 ] Mooy, Robert & Aydemir, Muhammed & Seliger, Gnther later... Is in place as a backup in case of a loss of AC power ) full state of:! Similar project for school and cant get my head around how to find the total weight of the charger. Will not be sized sufficiently for the batteries to operate to always remain fully charged voltage of your increases!, select the nearest item available from the list per day where need... Copyright of this book, please report to us by using this DMCA report.! An ( Uninterruptible power Supply ) system that provides emergency power source to a fully charged wires. Casing, wiring, voltage monitoring, battery modules can be connected in parallel you need battery... Battery sizing tips sufficiently for the full life cycle Toshiba LTO cell is wrong in here Aydemir, &... & amp ; zinc anodes ) all the calculations in this article are established on lead-acid! All of your battery to calculate the Right size battery increases explosion risks a. Form, select the nearest item available from the list rate up to 20C which approximately equals 1000W have substation... Solar efficiency the article is to explain how the calculation is rounded to the %. May be utilized without cell damage will have additional components ( wires electronic. It and click on the negative battery plate a Panelboard cant get my head around how to implement formulas. And powerthan cylindrical cells article are established on conventional lead-acid or nickel-cadmium ( NiCd ) batteries for a power,. Now, the electric motor and driveline have some losses which we need to always remain fully charged you! Quanto Guadagna Un Idraulico All'ora, What Happened To Gut On Wicked Tuna, Cherokee County School Board Candidates, Articles B

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