{"id":292,"date":"2021-04-13T20:32:43","date_gmt":"2021-04-14T04:32:43","guid":{"rendered":"https:\/\/denco.ad6dm.net\/batts\/?p=292"},"modified":"2021-04-28T12:07:31","modified_gmt":"2021-04-28T20:07:31","slug":"denco-milk-crate-backup-power","status":"publish","type":"post","link":"https:\/\/denco.ad6dm.net\/batts\/denco-milk-crate-backup-power\/","title":{"rendered":"DenCo Milk Crate Backup Power"},"content":{"rendered":"\n

This large 280Ah LiFePO4 prismatic<\/strong><\/a> build incorporates a milk crate<\/strong><\/a> as a carry\/protection container. It uses a 250A Daly BMS<\/strong><\/a>, to allow for powering a WZELB 3000w 12V 120V Pure Sine Wave inverter<\/strong><\/a>. This is the largest capacity battery build that DenCo has made to date.<\/p>\n\n\n\n

This battery backup power system utilizes a Victron Bluetooth SmartShunt<\/strong><\/a>\u2122 rated at 500A for monitoring voltage, amperage, and consumption stats on a mobile phone. It also uses a 300A resettable marine\/automotive circuit breaker<\/strong><\/a> as a sort of on\/off switch. It incorporates positive and negative 250A terminal buses<\/strong><\/a> for easy connectivity to multiple loads. All connections to battery, shunt, breaker, and terminal buses are with 1\/0 gauge welding cable<\/strong><\/a> to permit high draw applications. (Marine grade lugs<\/strong><\/a> were crimped with a TEMCo Hammer Lug Crimper Tool<\/strong><\/a>. Liberal use of zip ties and self-tapping #8 screws for mounting and securing items to the milk crate.)<\/p>\n\n\n\n

When originally testing the cell balance, I found that the first cell in series charged high and was 0.3V higher at BMS charge cutoff than the other cells. Because of this I also added a 4S LifePO4 Active Balancer Board<\/strong><\/a> that I had on hand to even out the cells when max charge was reached. Discharge voltage was fairly even during a 102Ah drain test.<\/p>\n\n\n\n

Total build cost: $1235.12 (not including crimper tool).
Total power: 3.5kWh at battery. With 85% inverter conversion efficiency (at worst), 3kWh estimated for AC power usage.
Total time for parts receiving to completed build: 3 months (mostly waiting for China shipments).<\/p>\n\n\n\n

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General Specs:<\/strong>
Created: April 11, 2021.
Cells: VariCore 280Ah prismatic 3.2V LiFePO4 cells, 4 cells in series.
BMS: Daly 250A 4S 12V common port BMS with fan.
Configuration: 4S1P (4 series).
Nominal Voltage: 12.8V.
Overall weight (with all components and inverter): 67.0 lbs (30.39 kg).
Current owner: AD6DM Dennis<\/p>\n\n\n\n

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280Ah milk crate #LiFePO4<\/a> battery with Bluetooth monitoring, circuit breaker, and terminal buses. This is my power outage backup system. All this effort to charge my phone \ud83d\ude1c pic.twitter.com\/x6Facnh6jD<\/a><\/p>— AD6DM Dennis (@AD6DM) April 12, 2021<\/a><\/blockquote>