auraslip said:
I charge on the road with power supplies.
They come in many flavors, but I always just charge at the limit a standard 15amp wall outlet breaker can sustain, which is around 11-12amps, which is roughly 1000-1200w charging.
Tiny. Compact. Light. Cheap. And unlike little toy chargers that come with an off-the-shelf pack, these actually charge at a power level that let's you add meaningful watt-hours back into the pack in a little 30min break for a snack or drink.
Man.... all things being equal a 1kw charger or a 1kw PS isn't going to be tiny, compact, light, and cheap. Bms battery has 900w chargers for $100 shipped. A 1000w meanwell is what? $200-$300(i just checked ebay)? And the meanwell isn't cc/cv. What you do you think about that? Am I too far off? And the meanwell requires some sort of baby sitting right?
I don't bother with meanwell's any longer.
$30 each. 48v @ 12amps, isolated. My around-town charger is a pair of them. It's about 3lbs for both, about 10"x4"x1.5" for the pair.
http://www.serversupply.com/products/part_search/pid_lookup.asp?pid=120608
My at home chargers are a pair of these 3kw chargers in series.
http://www.serversupply.com/POWER%20SUPPLY/SERVER%20POWER%20SUPPLY/3000WATT%20REDUNDANT/HP-COMPAQ/253232-001.htm
Run on AC or DC from 80-90VDC or VAC up to 280VDC or VAC. Like most modern switchers, it runs more efficiently on DC than AC, but only by a fraction of a percent (cap ripple losses).
To use, I just plug in the deans connector, and plug the other end into the wall. It can NOT over charge (if everything is adjusted and setup correctly obviously), it's got about a billion times better regulation on voltage than ANY battery charger on earth.
Does this not satisfy being cheap, small, light, compact, and simple??
This is how Methods, myself, and a handful of others have been charging now for the last year.
The only thing I use an RC charger for is my RC hobbies, or cycling/testing packs before building them.
auraslip said:
LOL
(assuming you're being sarcastic)
Lfp, I'm amazed by how often you can get away with being intentionally misleading and rude to forum members. Not only that, but you have business or other wise personal relationships with hobby king. Did they give you a tour of the factory because you got enough people here to buy their lipo packs?
OTOH, I do feel I was a bit unfair to lipo with regards to modularity, upgradibility, and volumetric density problems with lifepo4. I'm going to rewrite those sections as well as update the cycle life information with more detailed info.
You do seem to know the most here about of hobby king lipo, what do you know about any relevant life cycle testing of them or similar batteries?
#1. All ebike LiPo sales for the last few years all combined wouldn't be enough to make HobbyKing even notice. Hobbyking had no idea who I was, what ES was, or that ebikes were using LiPo packs. (I let them know though of course, but our volumes are too low to matter).
#2. I quit my job and Microsoft, knowingly taking a pay-cut, to help advance the electric revolution, and currently am working as a battery system engineer.
#3. Hobbyking's battery factory makes and sells approximately 300,000 LiFePO4 ebike batteries a year, which are for the Chinese ebike/escooter market. More than ALL the USA vendors for lithium electric bike batteries by more than an order of magnitude.
#4. To say LiPo has XXX cycles or xxx safety is f*cking retarded. FIrst off, LiPo comes in all different flavors, PingPacks are LiPo, the Chevy Volt and Nissan LEAF packs are LiPo, the A123 pouch cells are LiPo, etc etc. The longest lasting chemistries (<40,000cycles) I've ever seen have been LiPo, and the shortest lifecycle (<20cycles) chemistries have been LiPo. They come in flavors from extremely dangerous (like first generation LiCoO2 lipo), and fairly safe like LiFePO4, and extremely safe chemistries like LiMNO2 variants. When it comes to RC LiPo, there are cells that handle wicked overcharge and do nothing, you can stab and crush and smash them and they just sit there or maybe get warm. There are LiFePO4 round cells that explode into flames when you do similar things, it doesn't mean LiFePO4 or round cells are dangerous, it means some are made with safety-fixated design criteria, and some are not. The new 100C-200C 18650 LiFePO4 A123 cells (used by F1 KERS, Kilacycle, and military energy weapons) can explode like a mini-grenade if you drop them on something hard enough to make the case deform in the wrong way. Some RC LiPo packs get smashed into pieces and have no fire or heat, some get overcharged to 5-6v/cell and just sit there, etc etc. The early stuff was VERY unstable, it could just explode if you pricked through the foil it or overcharged it to 4.4v. It created a reputation that has lasted, dispite modern RC LiPo behaving completely differently than the early stuff. As far as hobbyking's LiPo goes, some of the 20c stuff is made from the cheapest formulas/ingredients etc, it's designed entirely around making a functional LiPo battery for an RC toy at the least cost. Treat them right ( low DOD's, no overcharge or over discharge ooops), and you may get 500-1000 70%-80% DOD cycles, or even 5,000 light 50% DOD cycles. Treat them badly and make some big charging/discharging errors, you may get <100cycles. Get a bad batch, you might just be screwed, it's the risk you take when you buy the cheapest. If you buy something using all cutting edge chemistry and engineering, premium materials and manufacturing with elaborate testing and quality control like a Nano-Tech, and you don't do stupid things to damage it (over-charge, over-discharge), you're going to see 4, and possibly 5 digit cycle life (in a case with very shallow DOD).