Cell technology has advanced a lot and the way the wires are connected is pretty reliable for both Luna and EM3ev. I beat the crap out of my batteries riding over roots at 20 mph with a hardtail bike and I have never had a problem with my EM3ev packs but that said, the fully potted packs that Luna now offers have got to be very rugged. The fully potted pack also has drawbacks...i.e. heat transfer so don't let the marketing BS fool you...there are goods AND bads. The EM3ev pack will only transfer heat marginally better...after all it is fully enclosed and the cells are glued together.
The BMS is now the limiting factor in most packs IMO...not the cells or the way the wires are connected.
Not sure exactly what Luna uses but EM3ev has a BMS that is Blue Tooth accessible for troubleshooting and data retrieval and will also do cell balancing at lower states of charge. Both the Wolf Pack at Luna and EM3ev 14s packs have a BMS rated for 50A continuous. The highest amperage cells Luna uses are the 30Q...which are rated at 15A/3,000mAh and with EM3ev you can get the HG2 which is rated at 20A/3,000mAh so I'd have to give the nod to EM3ev if you are after a small high power pack. If you don't need or want the high power, like some others have said, the fully potted wolf pack has to get the nod for durability. For high capacity Luna use the MJ-1 cell which is rated for 10A/3,500mAh and EM3ev uses the 35E (8A/3,400mAh) so Luna gets a slight nod for capacity. Want something bigger...in the 14s6p pack Luna only offers the MJ1 cells where EM3ev has a few choices including the PF, HG2, and 35E.
It sort of comes down to...do you want to pay less and wait a little longer for it to get to you from China with EM3ev or pay more and get it quicker with Luna. AND that assumes you live in North America.
Tech support...I have had more detailed tech support provided by EM3ev but just like shipping there is usually a delay. Not everybody wants or needs it.
If you are after really big power and can handle the increased size...the EM3ev 20s10p pack gets the nod but it is in another ball park from the 14s packs.
Neptronix's point helps tip the scales towards EM3ev for me but Luna has gotten a lot better and that fully potted pack has to be rugged...so it just depends on whether you like apples or oranges
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