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Karman de Lange

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  1. Plan was to just stick on my Revo balancer (8s) when I had time again, but Eksdom forced me into production .. so i'm just doing in place balancing Just hot glued them together , which is royal f-up. … thats problem with having to rush things... I thought of buying those 18650 holders, but works out rather expensive for piece of plastic, but def looks lot better.
  2. My issue is , I know how my life goes: "Yes, I will check battery's every week to make sure its balance" .. but that never happens, Its been in 2 days only and already forgot twice that I stuck charger on a cell to try get pack balanced .. .. (My pack was not balanced before forcing it into production). BMS on its way, ordered it yesterday only. Hopefully it works as advertised .. What capacity average did you end up per cell, mine is about 1.7ah ?
  3. Was thinking of the CCGX .. I know the bus its few ms, tested that ones accidentley
  4. Gumtree (pc recycling and 2nd hand pc/laptop guys) A few of the actual recycling companies will "sell" them as well, its easy money for them as they don' t need to actually recycle them. Just be carefull of stupid prices some charge as you get about 50% of usable cells only. I paid just bit more than what they would have gotten from recycling people (/kg).
  5. Glad you only heard of two …….. its daily occurrence .. If you did not know, there is reason why you can only ship lithium by sea , there been at least 4 commercial aircraft (freight) brought down by lithium packs catching fire, there might be even more as freight aircraft crashed don't really make the media. I've been selling Lithium and using lithium batteries for about 9 years now .. Have fair understanding of limitations and safe working parameters (never 100% guarantee, but i'm happy enough). The batteries will also be housed in my "power room" with the Lister and Victron inverters where if there is a fire, it cannot in theory spread to rest of the house. Re BMS/Linux: That why I bought a Batrium BMS and it works plug and play with Victron.. Victron also will shutdown if no communication received for 1 minute (If I recall correctley) from any monitoring system (its own controller as well).
  6. Hi, Ok, some info re "life expectancy". A manufacture regard 80% capacity as end of life. Most lithium packs do about 500 - 3000 cycles (2-10 years) if you partial cycle them (50-80%), then after those cycles you have 80% capacity left.. Now also, remember lithium gets damaged when fully charged , the opposite of lead acid that get damaged when not 100% charged Now we go buy "dead" laptop battery with "80%" capacity left and they have not seen any charge for years (so no extra damage really occurred). You test each cell by charging/discharging them and then sit them one side to see if they self discharge. Any cell below 4.0v after month go to the use for something else pile. If they get hot on charge, they go in bin immediately. Now the cell might have been 2500mah when new. Now its a 2000mah after 5-10 years of use (80%). That is still a lot for what we need, we don't care about weight etc, so can simply add more cells. Even 1000mah is perfectly fine if they don't self discharge and don't get hot on use. Its just double the amount of work (or triple of new cells). I used anything above 1300mah tested capacity . So our cells should give us another 5-10 years of use with only a reduction of 20-30% of capacity (of course, will only know that in 5-10 years). So in theory we will then still have 70% of our current capacity, which is still more than what we need. If I can get 5-8 years out of this pack, its same or more than Lead acid in real world and at 2% of the price with no worry making sure water levels are right, room is ventilated its a no brainer. There article somewhere about Tesla cars (same battery tech) and there battery life expectancy is 25 years with daily use, or more than the life of the car.
  7. Seeing that eksdom forced my hand, Had to install my pack this weekend .. Its about 180ah usable capacity at 1C and easily handles our 500w continues load and I ran the aircon few times , 1800w 80A at battery level, to check cable tempts etc. What the nice part is … after power came back on, took 40 minutes to fully recharge at 0.1c . I increased the charge level to 0.25 and we had a ~3 hour power failure last night and recharged fully in 1hr when power came up. The Pack is set to charge to 4.05v per cell (Lithiums don't like being charged to full capacity). Float at 4v. I also ordered a Batrium battery management system (cost double the price of the battery bank, but need a balancer that plug and play with inverters , no time to build own now) so will see how goes then. Then its to solder the other 500 cells to get pack to final size. Will also try do a full discharge to see what true capacity of the pack is , should be about 30% more than the 1A discharge tests as each cell now only see a load off about 0.05c at normal load .. so in total its should be about ~R 11k with management for a usable(not total) 10Kwah bank. So thats same as about 30Kwah lead acid bank (if my calcs are right ).
  8. Easy to source laptop battery's .. . just do gumtree search for people recycling pc's etc. Otherwise contact recycling centers, they sell by weight. I found about 800 packs within few days and just got it couriered. Busy doing my powerwall now, at 900 cells soldered now, probably another week or 10 to do the reset (1500 in total) . its a slow and very boring process to test 1500 battery's and then solder them all up. so be warned. Been busy about ~9 months already. So far +-R 5000 invested for packs/chargers/testers/wires etc , +- 520 ah (tested) capacity (~2kwh ). Lot cheaper than any other method of doing it.
  9. 2 x Victron Multiplus 1600 24v + CCGX monitor unit. Currently in production and working 100% . Falls under 5 year warrnanty, bought in begining of 2015 Reason for selling; Want to upgrade to >5kw unit Willing to split R 30 000 onco
  10. 16 x Enphase grid tie micro inverters + Envoy monitoring unit for sale. It is compaitble with a islanding system (frequency shift) 2 x ME215 14 x M250 1 x Envoy Unit All cabling. Currently in production and working 100%. Reason for selling want to go MPPT R 25 000 onco
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