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  • Posts: 4
  • Registered: ‎06-18-2010
  • Location: Singapore
  • Views: 52
  • Message 1 of 1

Charging 2 9-cell 7.2Ah batteries from Brunton solar panels thri Multiple Battery Charger

2010-06-18, 12:10 PM

Hi all fellow ThinkPaddlers! I am attempting to run my T40 from solar and this is one ambitious project but I felt charging 2 large capacity spare batteries seems more practical. I always left home in the morning and get home in the evening and I thought it's ideal. I thought about this setup but I wonder whether it would work or not. (I hated paying too much to my national sole utility provider for the electricity, and also because I didn't snag a job through an interview with them, gggrrrrr, so less profits for them is my objective!). Besides, I'm in sunny Singapore so I thought of getting energy from the sky instead of paying companies to burn palm oil, natural gas and all that crap that cleared forests in Malaysia and Indonesia.


Anyway, I am thinking of getting three more 9-cell batts to add to my existing 9-cell and I intend to use 2 of them while I'm roaming outside to "play" my T40 and the remaining 2 to rest at home to get charged from 2 26-watt 12v Brunton solar cells, running thru a 12v 4.5A controller regulator and a car adapter and then thru the Multiple Battery Charger II (Part number: 22P9040). initially, I thought fantasy of it but when I read the specs of each component and calculated them, I was very skeptical of getting my 2 9-cell charged for one day.


Layout goes like this: 2 or 3 Brunton 26w 12v PV panels -> 12v 4.5A solar regulator -> 120w dc-dc car adapter (Vanson SDR-120w) selected to 16v 3.5A -> Multiple Battery Charger II -> my 2pcs of 9-cell 7.2Ah batts


I calculated that I could only get 6Whr from this setup from 52w (assume) PV panels because it involves several components along the line and the Battery Charger saps energy heavily. Therefore, I thought I could end up spending 18-19 hours charging them.


The multiple battery charger 22P9040 on Lenovo website mentions that it charges with voltage of 12.6v OR 16.8v and with a current of 3.9A. I'm no electric genius and I have no idea which one is applicable for my 9-cells.


Anyone tried this or is using this setup? Pls help!

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