OK, anyone know where to buy packs north of 12 volts, i.e. 5 or 6 cells and probably 5S2P or 6S2P ?
Alternatively I could use the 123 size and find holders… but rather a single pack.
Seen some prices, pretty expensive…
Not interested in “ordinary” LiIon or LiPoly, please don’t waste the thread… I know some of you out there are battery experts…
Greg
They are kinda spendy, aren’t they? $54.00 for a 16v 1500 mAh battery? They must be really proud of it. (https://largescalecentral.com/externals/tinymce/plugins/emoticons/img/smiley-laughing.gif)
https://www.batteryspace.com/custom-lifepo4-18650-battery-pack-16v-1500mah-24wh-2a-rate-5s-s.aspx
Whatcha got in mind?
Greg…It will all be mute once element MC #115 hits the market.
Greg,
What’s the application? Capacity? 4 cells makes a 12.8V battery with LFP. Are there weight and physical constraints?
I don’t have much experience with this technology, came to fame after I de-trained at Lithium Manganese.
Michael
Steve: thanks, that’s about the only site I can find with pricing and voltages I like.
Michael: As in my first post, 5 or 6 cells… I know they are 3.2 volts per cell… no weight or size restrictions. it’s going in a Bachmann Emily tender, which is empty and about the size of a refrigerator.
So, just looking if someone has found a reasonable price other than a $70 pack.
The loco will switch from track power DC/DCC to Revolution DCC. It runs really fast, so looks like the 2 pack configurations I put in the first post would be fine. Need to double check with Navin on minimum voltage on the Revolution DCC, pretty sure 12.8 will be too low… especially after the drop through the Revolution.
Looks like the simplest way is 6 cells of the 18650 or the 26650 (about 3.3 ah each) for about $10 each…
Hmm… seems about same as the regular liion packs… man this battery thing is expensive! Need a charger too… hmm… adding more power pickups is sounding better and better, maybe a keepalive cap for the Botchmann DCC board.
Greg
I think you’ll have to grin and bear it Greg… LFP cells are not widely available as compared to Lithium-Ion and Lithium-Poly. The LFP cells while claiming to be more robust with regard to life cycle claims of 2000 or so, require a more sophisticated BMS/PCB. As I understand these cells tend to discharge at varying rates requiring a Battery Management System. Cells and BMS/PCB appear to bring a premium.
As you note a technology specific charger is required, in other words a Lithium-Ion/Poly charger is NOT compatible with LFP cells. I haven’t bought a battery charger in many years, yet I have at least one from Hesperian that supports all the atypical technologies including LFP. I purchased a couple of LFP batteries several years ago (different sources/brands at different times), initially they performed as specified, yet both failed early in their life cycle and I haven’t been down that road since.
Not to belabor your comment on not wasting the thread on Li-Io or Li-Po why are you excoriating same? I’m thinking myself and others are interested in your reasoning.
Michael
No excoriation of lithium ion or poly happening here at all…
1 : to wear off the skin of : abrade
2 : to censure scathingly
(severe criticism to the rest of us)… there’s no criticism of those chemistries at all, not in the least…
I wanted to try one of the “safer” formulations… i.e. the claims of no thermal runaway if damaged, and better tolerance to overcharging.
Looks like it’s no extra cost over regular lithium technologies, since I would have to buy a charger in any case (my other chargers are more set up for lower voltages and fewer cells)
This battery power stuff is not cheap when you start out… I see why people get defensive because of the investment up front. I’m having a hard time dealing with $120 in a loco that already has track pickups and the DCC decoder only cost $90… but I see if I standardized on voltages and chemistries the chargers would not have to be one for one.
Greg
p.s. sure do love your avatar Michael
Greg,
Perchance my effort to elucidate your statement of “LiIon or LiPoly” was ill spent bemusement. As you allude to above, LFP cells are purported to be a “safer” technology.
Are you thinking of purchasing a battery or assembling your own? The BMS-PCB’s are in favor for LFP, yet fall short of providing the end user a snapshot of the battery/cell condition (I noted not all LFP battery offerings employ BMS-PCB’s). If it were me I’d take advantage of chargers with “balance pigtails” and purchase or add balance pigtails to my battery.
In my circumstances, I endeavor to make the batteries easily removable verses permanent installation. I play with trains, planes, cars and drones, batteries see use across my continuum.
The KM Hydraulic of my avatar was an imported state of the art purpose built offering/oddball, of which SP entertained long enough to set aside sooner than later. I have a few 1/29 scale kits of same, I hope to assemble them in the near future working on F3 conversions to F7 now.
Michael
Greg Elmassian said:
excoriated;excoriating
transitive verb
1 : to wear off the skin of : abrade
Thank you Greg… I have learned from this thread that my 18yr old son possibly has an issue with excoriating in the shower !
Michael Glavin said:
The KM Hydraulic of my avatar was an imported state of the art purpose built offering/oddball, of which SP entertained long enough to set aside sooner than later. I have a few 1/29 scale kits of same, I hope to assemble them in the near future working on F3 conversions to F7 now.
Michael
Krauss is dead but I’m curious to the noticeable “exterior” differences between the 3 and the 7 ? Will it include extra junk and then possibly be converted to a 9 and then an FL unit which gets replaced by the ?
Greg Elmassian said:
OK, anyone know where to buy packs north of 12 volts, i.e. 5 or 6 cells and probably 5S2P or 6S2P ?
Alternatively I could use the 123 size and find holders… but rather a single pack.
Seen some prices, pretty expensive…
Not interested in “ordinary” LiIon or LiPoly, please don’t waste the thread… I know some of you out there are battery experts…
Greg
Would this fit your needs?
https://hobbyking.com/en_us/zippy-flightmax-4200mah-4s1p-30c-lifepo4-pack.html?___store=en_us
As for a charger I can recommend these I have 3 running off an ATX power supply modified to be a bench top PSU they do my NiMH batteries as well as my “Graphene” batteries.
Graeme, how many volts are available in that 4200 mAh “Zippy Flight Max?”
Greg, I charge my 3200 and 6000 mAh LIon batteries at 1500 mAh. Takes longer, but no worries.
" Rooster " said:
Michael Glavin said:
The KM Hydraulic of my avatar was an imported state of the art purpose built offering/oddball, of which SP entertained long enough to set aside sooner than later. I have a few 1/29 scale kits of same, I hope to assemble them in the near future working on F3 conversions to F7 now.
Michael
Krauss is dead but I’m curious to the noticeable “exterior” differences between the 3 and the 7 ? Will it include extra junk and then possibly be converted to a 9 and then an FL unit which gets replaced by the ?
Rooster, I’ll work on a post in the near future with regrard to my USAT F3 to F7 conversion rather than muddy the waters herein.
Michael
Steve Featherkile said:
Graeme, how many volts are available in that 4200 mAh “Zippy Flight Max?”
Voltage: 4S1P / 13.2v
Graeme, thanks for the link… I think I have to go 5 or 6 cells as I stated (but you are right 13.2 is north of 12 volts).
5 cells would be about perfect in LiFepo4, but they only have 4 cell packs…
Good link though, forgot about them, they have everything. I can easily get what I want voltage wise in ordinary LiPo…
Greg
