I'd say the main issue is still QC (or lack thereof). If RC Lipo cells (and packs made from them) were as consistent in quality as the name-brand 18650/etc cells, they could be trusted as much as those are.Sunder wrote:I agree, these packs are becoming so good and economical, I'm not sure why more people aren't using them. Maybe for cars, hard cased cylindrical and prismatic cells might be better for impact resistance and thermal dissipation, but for eBikes and stationary packs, I'm hard pushed to see why people still prefer cylindrical cells.
And sometimes the cells themselves are of questionable origin, making the problems even worse.Hillhater wrote: 18650s generally result in dozens of cells being assembled by enthusiastic amatures into complex packs employing hundreds of untested connections and wiring runs, wrapped in Duct tape etc .
Whilst the cells are reliable, the quality, and often design, of the pack construction is highly variable
The MultiStars are clearly an improved product that is actually less costly, despite inflation, than the Zippy; 25C's and Turnigy 20C's that were the defacto LiPoly's a couple of years ago.Ive got plenty of refunds by registering my packs for warranty and supplying them the information as soon as I discover it....-icecube57
Users only need to be reasonable w/ their system discharge C-rates.The 10C Multistars are set up for the very important Quadcopter market and are apparently higher quality cells than the 20C RC packs. I've had really solid performance from my Multistars at 2.5C-Alan B
I think it's time for folks to stop judging the MultiStars based on their experiences of the "ghosts of LiPoly past".Im running 66v 32AH on a Mxus 4T. They are running great. Never need balancing. Always within 0.01v of each other. Excellent performance. I havent did any capacity loss checks lately.. mainly cause Im not pushing them to empty every time because its a huge pack. I charge mine when I need it. Leave it discharged until the next ride. I store them in a cool area. the 16AH are 2p. meaning two cells are in parallel so they have a lower IR and can put out more power with less voltage sag. These are ok to 4-5C I haven test the 20AH but the reports are they are 1p. Normally larger AH cells have a lower IR too but I tested the 10AH cells which are 1P and they were only good to 2.5C so I transfer those same specs to the 20AH. So i suspect the 20Ah are only good for 2.5C as well. -icecube57
For my part, I'm discussing all the RC LiPo in general, not any particular brand (none is mentioned in my post). It was in reply to Sunder's question that implied commercial use of RC LiPo in manufactured products (vs DIY stuff by hobbyists).motomech wrote: I think it's time for folks to stop judging the MultiStars based on their experiences of the "ghosts of LiPoly past".
I'm charging 4 of the Multi 4s 10ah batteries at 1c, like you should. Higher charge rates aren't the best for the batteries and I've tried to stick to that. A few years ago, I would have agreed with you, but the cost of round cells has almost reached parity with the lipo packs. I bought a bunch of the 4s 10ah batteries for $25, now they are around $40 on sale. Even doing a 48v 10ah pack you are talking around $140 with shipping. Add your $100 Meanwell charger, 3 - $30 battery medics and the total is $330. I can buy a 48v 13 Ah LG pack for the same price including the charger shipped. Yes, lipo is lighter and smaller, but a pound or two doesn't matter much on an ebike with 3kw. Right now prices are comparable.I said they are lighter, smaller and less costly than round cells, I, for one, never said they are better.
It is well documented here that Multistars should be used in a lower-discharge system and if you can get a higher discharge rate from a "Dolphin" battery, I can only say that you must not be carrying much capacity. Part of the beauty of the Multistars is that since they are smaller and lighter, more capacity can be carried for a given space.
I wonder if you have optimized the charging procedure for LiPoly I am on record stating that they should be bulk charged and that the pack should not be constantly "broken down" to charge. And If it takes "one to two hours" for you to go from 3.90V/cell to 4.10V/cell, I can only surmise that you are still using a low-powered RC "toy" charger. I can take my 20,000 mAh pack to top Voltage in 20 minutes using a Mean Well HLG power supply.
I''m not sure it's fair to criticise the Multistars without detailing how you are using and charging them
And please It's tedious to read "blowing up" comments without any relevant examples. There isn't one report of Multistars catching on fire here, let alone "blowing up. More garages are burnt down w/ a gallon of gas than LiPoly.
Only if you don't finish the job. On that bike, a center frame bag could have been used;Lastly, you get a bike like this using lipo: