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Nov 05, 2024

How safe are lithium iron phosphate batteries? – pv magazine International

You need what is called a Faraday Cage. Remove the BMS from the battery. Wrap it in aluminum foil completely, folding over the edges. Now a note re BMS systems:They ALL draw some parasitic current

You need what is called a Faraday Cage. Remove the BMS from the battery. Wrap it in aluminum foil completely, folding over the edges. Now a note re BMS systems:They ALL draw some parasitic current even if only a few microamps. I lost a 1kwh 25.6 volt LFP pack 10 years ago. I didn’t realize the BMS started drawing excessive parasitic current.This was a custom pack I had made for a project, and cost $500. Pack totally ruined. I disassembled one cell with 0.1 volts remaining. The copper anode was totally corroded, and I could see a coppery color on the cathode.Very expensive electroplating. So a year ago I built my own pack for $80 thanks to Battery Hookup in PA. Great prices. My BMS is now connectorized, 2P8S, so 9 pins. Long storage I disconnect the BMS.To test for parasitic draw charge battery and let it sit for a week or so. Verify that each cell is within 0.01 volt of each other. Using a digital multimeter set to current, break the connection between each wire and battery taps and measure the current. For your 100 ah pack I would like to see all currents below 0.001 Amp,ie 1mA. So at 1 mA you will lose 1 AH in 1000 hours, or 100 AH in 100,000 hours. Each year has 8640 hours, so if each cell has less than 1 mA leakage current, you should be OK for years without having to charge. BUT I would check each cell voltage every 6 months to be sure. If I had done that I would have written off a $500 battery.Hope this helps