HOW TO DO SOMETHING (Website or RC related) How to – RC related cell type required to build ZOHD Li -ion 7.4v 2SIP- 18650 Battery

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    • #8606
      DavidW

      ZOHD Batt rec for echine razor glider are not available in Aus at present. An equivalent batt pack can be constructed from 2 cells welded together. My question is Are Panasonic NCR 18650 GA, 3.6v 3500 mAh , discharge 10A, Ht 65 mm, dia 18mm, Li ion, suitable for constructing an equivalent of the recommended ZOHD Lion pack 7.4v 3500 mAh 2SIP-18650?  These Panasonics have similar coding to the Sanyo cells that form the Zohd battery pack.  The Panasonics are in stock with Ausbatteries . com at a price of $ 23-90 plus p0stage in Aust.

    • #8607
      Ron

      Hey David, I can rustle up a couple of 18650 LiIon batteries and you can have them if you like. They are not brand new but would probably work OK in your ZOHD. I don’t have a welder but if we are lucky, they might already be welded together. Did you want to give it a try? I’ll start looking to see if they have a part number so we can work out what their capacity is.

    • #8608
      Ron

      David, here is the battery pack which would contain 6 batteries configured in 3 x 2 pairs where the pairs would be welded in parallel. New rating of the parallel pairs is 5.2 AH so individual batteries would be 2.6 AH.  If you want to have a go a dismantling the pack, you are welcome to it.  I’m not sure how old the pack it but you never know. They still might be OK for the ZOHD. If you are lucky, you’ll get three battery packs out of it 🙂

    • #8609
      Ron

      Silly me, I just re-read your email and I have my parallel and series mixed up. You should still be able to recover them in series to make 7.4 v and the current would be 2.6 AH.

    • #8624
      Uncle G

      David, Yes they are the correct cells but I use the Samsung INR18650-30Q they are 3000 mAh but are rated at 15 amp discharge where the Panasonic/Sanyo are only rated for 10 amps but are 3500mAh.

      These batteries don’t have as big voltage sag on load like the Panasonics. (dropouts on take off!)

      I wouldn’t recommend the Laptop batteries as they can’t deliver enough current.

      I have a battery spot welder, so can make up packs for you.

      Panasonic and Sanyo are the same batteries just branded under two different names.

      Another option is to use a LiPo battery, 2S 1100-1500mAh

    • #8625
      Ron

      Thanks for your input Uncle G. I didn’t know laptop batteries wouldn’t deliver enough current.

    • #8626
      DavidW

      Many thanks Ron and Uncle G for you replies to my query. There seems to be a wealth of knowledge and generosity in our group. Given my total lack of knowledge of things electrical I will chase up the cell purchase option and have a discussion with you  prior to unleashing things that go flash bang in the night. I have the one ZOHD battery bought from Hoppy and now have rigged my charger up with 12v leads to connect to my ute battery so i shall have reasonable air time for the moment. The motor cut out on launch I  experienced was resolved by Predator and Uncle G as voltage drop on the ZOHD batt and has been prevented by limiting motor to 35% max power.I believe Moose has his limited to 15%  and his is flying well. Thanks again.

       

       

    • #8627
      Hoppy

      Dave, for your needs you should buy LiPo packs. Lion are for long single flight times such as long range FPV.

    • #8629
      DavidW

      Ta Hoppy, several have suggested LiPo. At moment i would like to stick with what i am familiar with until i learn to fly the beast. Will have to consider LiPo for the next aircraft and bone up on their use and maintenance at that stage.

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