I am very excited about this chemistry! This might break the proverbial camels back to the barrier of accessible larger heli power systems. No doubt, they may force LiPos pricing structure down should they prove out.
1. Currently sold only through Ebay and a few small sellers as the 28V pack for the Milwaukee power tool line. I have seen 2 V28 for about 190.00 US Bidding has made their prices difficult to track due to supply and demand.
2. The 28V milwaukee pack should be available at Home Depot and Lowes soon.
3. You have to buy the 28V pack with the charging circuit and case, dismantle it, and rebuild you packs using the indivual cells and a soldering iron. This used to be the norm for us old eheli pilots. The manufacturer has made it very very clear that they will not take on the liability of selling individual cells. Give it time, money changes everyone.
4. The cell are round ca. full C size with steel incasement. 100 g each. As such, they weigh a little bit more than the poly-pillow packs of LiPOs such as TP or tanic. No solder tabs Their size mandates a strategy when fitting them to some airframes. A few break the 7S into 1 3S and 1 4S (in series) using a contructed wireharness to link the circuit with kits that just dont fit them well Usually its a CG thing. Cell voltage is the same LiPos at 4.2 V/cell.
5. Power output and power density are not quite as good as the performance Lipos, but they appear to be very robust as by survivability manefested from several crash reports over on rcgroups.
3000 mAH cells are rate at 15C cont/20C burst - I believe. They hold there voltage during discharge very well.
They can be charged safely at 3C!
6. They are very new so the true longevity of the cells is not yet fully explored.
7. I have seen many request to coax someone to delibertly test the consequences of overcharging, overheating, and general abuse, but have yet to see any reports.
8. By the prices I have seen they appear to be one half the price of the high performance LiPos currently out there, but again their halflife is unknown.
9 Current airframes giving positive reports include: Swift (4S), E-raptor conversion, 1 Evo 50, and an eRaven. I dont know about the micro sized birds such as the TREX or blade - probably not, but the lipos needed for these birds are comparitively cheap to the required cells needed for the 50- and 90-sized airframes.
10 They are charged using a LiPo charge profile and yes, most are incorporating balancing taps and a balancer into the cycle regimen.
To give proper due credit to the pioneers subjecting their helis for the betterment of us all: Al, Ozace, Gary Goodrum and a few others have really stepped up the OT on these cells as logged in several threads over on RC groups. I apologize to those names I have forgotten.
Stay tuned, I will build a few packs for my bird asa they can be bought at Home Repo.
Brian
Formally Known as Giheli- Team Dyson Member
