Hey its 5am so this may have been mentioned 5 times but my blurry eyes missed it.
I have a 24v 20ah (most well known branded but better not mention) lifepo4 pack. I asked the vendor if I could charge via solar. This was years ago before Id got very deep into battery technology etc. I asked about the wasteful inverter idea and He replied
"Actually, you don’t need to use an inverter with our charger. You can charge the
battery pack directly with a solar controller or DC-DC converter that can output
28-30v. It will be more cost effective."
I never tried it but I guess he just meant Run a regulated 28-30v directly in place of the 240v/30v mains charger. The shunts and wotnots on the bms thingy will do its job. He never mentioned ampage but I only had a 40w panel anyway.
I do not like the bms and actually use a 12v RC balance charger (cellpro 10s) and cheap voltage monitor instead. http://www.rcsmart.com.my/webshaper/store/viewProd.asp?pkProductItem=5856(£2 on ebay). I dont like the way it bounces the cells up to 3.95 for hours while trying to balance the very cells the draw of the bms has created. Might be my imagination but I suspect the bms draws on one end of the battery pack as one end is always down if iv left it sat for a while. If I want to I can put my cellpro 10 on my 12v 40ah sla that charges via solar. In the day this gets about 2ah from the sun and 2ah from the lead acid so worse case is you take 20ah out of my 40ah reserve is was in a rush to charge it
Word of warning about inverters. I fried a big ni-cad pack and a camera lithium battery doing this. Its a big brand 500w modified (not pure) sine wave 12/240v model. I guess the frequencies are too rough or something complicated but they never charged properly again.
I have a 24v 20ah (most well known branded but better not mention) lifepo4 pack. I asked the vendor if I could charge via solar. This was years ago before Id got very deep into battery technology etc. I asked about the wasteful inverter idea and He replied
"Actually, you don’t need to use an inverter with our charger. You can charge the
battery pack directly with a solar controller or DC-DC converter that can output
28-30v. It will be more cost effective."
I never tried it but I guess he just meant Run a regulated 28-30v directly in place of the 240v/30v mains charger. The shunts and wotnots on the bms thingy will do its job. He never mentioned ampage but I only had a 40w panel anyway.
I do not like the bms and actually use a 12v RC balance charger (cellpro 10s) and cheap voltage monitor instead. http://www.rcsmart.com.my/webshaper/store/viewProd.asp?pkProductItem=5856(£2 on ebay). I dont like the way it bounces the cells up to 3.95 for hours while trying to balance the very cells the draw of the bms has created. Might be my imagination but I suspect the bms draws on one end of the battery pack as one end is always down if iv left it sat for a while. If I want to I can put my cellpro 10 on my 12v 40ah sla that charges via solar. In the day this gets about 2ah from the sun and 2ah from the lead acid so worse case is you take 20ah out of my 40ah reserve is was in a rush to charge it
Word of warning about inverters. I fried a big ni-cad pack and a camera lithium battery doing this. Its a big brand 500w modified (not pure) sine wave 12/240v model. I guess the frequencies are too rough or something complicated but they never charged properly again.
