Agreed the PL8 is a better unit, but given that I already own a Hyperion, I might as well use it, at least until it dies... If the Evassemble chargers wouldn't be good, are there any alternatives that you can think of to do a similar job of being a travel / emergency backup charger?
I'd be looking for the following -
1. Mains powered (110V 60Hz for me, better if also able to deal w/ everyone else's power as well...)
2. Compact - comparable to a 'mobility brick' or smaller...
3. Cheap...
4. Able to balance an 8S pack
BAD NEWS - Plot complication!I just discovered a complication.... The H-frame chairs basically have two plastic battery boxes, each nominally sized to fit a Group 24 battery. The two boxes slide into the frame, and connect to each other and the chair electrics with guided SB-50's that are part of the lids on each box. It's a decent setup, but would be very difficult to change as it would require modifying the mount for the SB-50 on the frame of the chair, and probably have a lot of other dimension / fitting issues...
I'd been assuming that I could build the Group 24 packs like you describe in the conversion page, and be all set. However I actually started taking measurements a few minutes ago, and discovered that I have a fit problem... BCI height for a Group 24 is 225mm, and MOST of the box is 243mm high inside, but there is a cutout in the center of each side for the Anderson connector that is only 224mm high - obviously they assumed that the battery terminals would be on the ends of the battery, so they'd have clearance in the middle to use for the SB-50's, fuse box and wiring...
The problem is that the Group 24 size pack is 6 cells high, and 6 x 40mm = 240mm, so there would be no room for the SB-50's
This leaves me looking for alternatives....
1. Obvious is to go for the Group 34 setup - lots of room, but it is only 4S7P, using the 12Ah cells I get 84Ah, which is not much better than the nominal 70Ah of a Group 24...
2. Since the problem is only in the middle, I could go to an odd-ball setup by adding two more cells on each end, so I end up with a 4S8P pack, for 96Ah
3. I also looked at the 15Ah cells - it looks like I could stand them vertically, which would give me a 4W x 6L pack that would be about 185mm tall, and be 4S x 6P, for 90Ah
Seems like the winner per the standard rule of cramming as many Ah as will fit in the box is number two.... if I compare costs, option 3 is about $60 cheaper, but that isn't much of a difference given the total cost for either choice...
It does look like the 15Ah option is actually a better alternative if one does need to fit in a Group 34 size box (assuming it is sized to fit the BCI spec)
One of the questions is EXACTLY what are the dimensions of the ASSEMBLED cells in blocks... The dimensions given are for single blocks, but supposedly they lock together with dovetails - sort of like the Anderson PowerPole connector shells... if a small part of each block is keyed into the adjacent block, then several blocks in a row will be shorter than the total of that many blocks measured separately... So how much of a difference is there?
On a similar line, I can't find a number for how long the 15Ah cells are in blocks - I reached the 184mm value I assumed based on the idea that the blocks add 32mm to the length of the smaller cells, and using the same addition on the 15Ah cells...
Thoughts?
ex-Gooserider
Burgerman wrote:Best setup today is PL8v2 and some high or low power supply from 12 to 30V.
Since you understand the wiring, you could use that setup at home, but use a generic BMS and only use the charging part of it and bypass the rest for travel with a dumb charger. Just be sure to use one that is at a lower voltage than recommended, at say 3.5v per cell to stop it bouncing them off the ceiling, and be sure the pack is well balanced with a real charger beforehand..
