| Author | Message | ||
     Torquehd |
Well after 2 years of mostly not riding my Shorai is officially dead. My battery tender wouldn't charge it enough to start it so I put it on a 5 amp conventional charger (which I know is not recommended). Got it started, took it for a ride, put it immediately on the tender and a week later it won't start again. Has a surface charge enough to run lights but won't turn the starter. It seems like AGM's are better at bringing them "back from the dead" as far as being able to hold a charge after being dormant for long periods of time. Opinions on this? I've only ever used HD and Shorai batteries. Any other recommendations? | ||
| Hootowl |
Try a charger that has a 'repair' mode and that also charges lithium ion batteries. Noco makes them. | ||
| Greg_e |
There is no repair mode for the lithium batteries. You could try running it down with a light, and charging again, but it's probably toast. What I would do is open up that Shorai and see exactly what is inside. After I see that I might have a plan of action to suggest that might get you going for as little as $75 and Lithium. Contrary to what people may recommend, I do not suggest Scorpion batteries. I bought one, my brother bought 2, none of them lasted more than a year! | ||
| Greg_e |
The few images that google was able to cache show that Shorai does not use a low voltage or high voltage cutoff. That means you could probably make a pack yourself, and do it better than they did. https://hobbyking.com/en_us/zippy-flightmax-8400ma h-4s2p-30c-lifepo4-pack.html This would be about the same capacity pack. But I would go at least two of them in parallel to double the real capacity to 16 amps and more than 400 amps short term. For my harley I was thinking 3 packs to keep the alarm working, and would give around 700 amps for many seconds. That said I bought an Everstart agm from Walmart for my harley for now. | ||
| Torquehd |
I'm not smart on Li batteries. So... if discharge is "30C", does that mean 30 x 8400 mAh or basically 250 CCA? Is that apples to oranges? IIRC, each individual cell must be charged seprately. Can you just slap two of them in parallel, without some type of management circuit? Now i'm going to do some research on Li batteries. It would be awesome to have a couple smaller batteries decentralized instead of a big heavy brick. Even though the Shorai is light enough at ~5 lbs. (Message edited by torquehd on September 16, 2017) | ||
| Greg_e |
Far as I know they will sort of self balance. Remember that they are fragile, so I'd keep them in a box. Those packs will actually handle 40x for a few seconds, that's a lot. | ||
| Hootowl |
"There is no repair mode for the lithium batteries" Then my owner's manual is lying to me. | ||
| Greg_e |
It probably is, the failure mode is generally to puff and die. I should load check my Shorai and see if it still has capacity, might have my own donor. | ||
| Torquehd |
Greg what Shorai are/were you running? I initially bought an 18L1 but had poor cranking performance so Shawn sold me a 21L6 which worked much better. | ||
| Torquehd |
Well i went to the local HD dealer and paid the devil for an AGM. It's a big heavy behemoth but I won't have to worry about burning the house down using an expiremental RC LiFe or LiPo battery. While I was there look what I found... now where on earth did they get this color scheme? Slap a blue oval on one of these and it would just about pass as a Buell jacket.  I do still need to learn more about Lithium. Individual cells do need to be balanced and maintained independently, from what I was reading lastnight. Guys have been getting away with using A123 batteries and balancing them before assembling them, and then trusting the vehicle's charging system to keep them mostly in check. They're a little bigger but a lot less fussy/dangerous. But that's still going to run you over $100. | ||
| Greg_e |
A123 is the same chemistry as that pack I linked LiFePo4, they are supposed to be safer than lipo. They also happen to run a voltages that work for car batteries in the 4s configuration. So what's happening with your dead shorai? | ||
| Torquehd |
Well it's not heavy enough to be a doorstop and too dead to serve any auxiliary purpose. I'll take a cutoff wheel to it if I'm not too busy this week. I need to research Lithium charging. I still don't have a handle on charging and balancing cells. If they're all hardwired together how can you charge one cell at a time? Greg, what size Shorai were/are you running in your presumably Buell? Off to youtube I go. | ||
| Greg_e |
I think it was the 21, but don't remember. It was close to stock size. Balancing can be done with passive "blinky" balancers, they just use energy to lower a high cell down to match the partners. Really should have and LVC and OVC, but finding one that allows 300 amps to pass is exceptionally expensive. Be best to build I've with relays for the output. | ||
| Torquehd |
So one of my coworkers minored in electrical engineering. I talked to him about the LiFePo batteries. He advised that you not run one of those unless you have a circuit to control the charging to each cell. He said the vehicle's charging system would charge it just fine but without some type of control unit regulating each cell you're potentially asking for trouble. So... there's got to be some type of "chip" or programmable circuit that you could plug into the battery to keep it safe. Apparently charging voltage is supplied through the "big leads" but the smaller leads are just for the computer to control each cell. (Message edited by torquehd on September 18, 2017) | ||
| Torquehd |
I think you'd need something like this https://hobbyking.com/en_us/6s-li-ion-pcm-charge-4 a-discharge-10a.html But it would need be specific to the appropriate input and output voltage and number of cells... | ||
| Greg_e |
Ideally you would have a big BMS, but try to find one with a 600amp capacity for less than the price of 2 Shorai batteries. This makes me think that they don't have any circuits in there. I know that they don't have an internal balance capability, but that can be handled by a small "blinky" balancer which is resistors and LEDs. | ||
| Jaimec |
Back to the original question: For AGM batteries, I think Odyssey probably has the best reputation (it's what most BMW riders use to replace that stupid OEM gel cell they used to use). I've also had decent luck with WestCo when I couldn't find the right sized Odyssey battery. | ||
| Hootowl |
I hear Duracell is the bee's knees too. https://www.batteriesplus.com/battery/motorcycle/b uell/m2-cyclone/1200cc/2000#finder-box-top Good reviews. | ||
| 86129squids |
+1, Odyssey. Fires my old Beemer nicely, ordered online. | ||
| Tootal |
Odyssey doesn't make the correct size for a Buell. An XB anyway, not sure on a 1125R. Great battery's though! I modified my battery box to fit one. | ||
| Torquehd |
Opened up the Shorai today. Nothing is labeled, and I'm an uneducated redneck, so I have no idea what I'm looking at. It appears that there is an integrated cell management circuit, IF you use the port that's covered by the grey plastic tab between the main POS and NEG terminals. Which I'm guessing, most people don't.   It looks like 8 "cells" or indiv batteries but only 5 leads. I can't remember how that works. 4 of the 5 are + and one is -... or vice versa? Maybe I'll split it up further and look for series/parallel wiring later. | ||
| Torquehd |
Ok, here's a better pic of the circuit board on top of the 8 cells. 8 cells, 2 each in parallel. So cells 1 and 2 are in parallel. Those are in series with 3 and 4 which are in parallel. Now put two of those in series and you get 8 cells.  Edit: So each balance lead looks like it discharges/manages 2 cells in parallel. Seemingly, each cell is not individually balanced; each pair of cells which are in parallel are balanced as single units. IE, 1 and 2 are both on the same balance lead. (Message edited by torquehd on September 24, 2017) | ||
| Greg_e |
Looks like you understand it very well. The important thing is no LVC or OVC protection, you should be able to throw a couple of those hobbyking packs in there and have a better battery. Buy a decent balance charger while you are there, or a simple blinky balancer and you would be set. I should cut mine open because it was dead and wouldn't trip my balance charger until I forced some charge in with the lead acid profile. I bet it looks just like yours, all puffy and dead. | ||
| Torquehd |
Thanks Greg. So I read an article earlier today, if i understand this correctly: Charging voltage comes in on the big terminals. If you have the RIGHT charger, the computer manages each cell by discharging higher-than-avg cells while the rest are still charging. Some circuits can even redirect voltage from higher cells to lower voltage cells. Mine wasn't puffy until I cut the shrink-wrap. Now i have a little bit more understanding but... my brand new HD AGM will last for the better part of a decade if I ride it regularly. So... unless I get a wild hair and decide to start spending money to cut weight, I'll probably stick with what I've got. Dang it. | ||
| Torquehd |
And I pulled off the circuit board that was on top of the battery, that the balance leads feed into. I had hoped that there wasn't actually a circuit, but each lead would be direct-connected to the charging terminal. I was wrong.  The components that say "101"... they look like little IC's, but I'm thinking they may be resistors? EDIT: So, thinking about what I'm seeing... I think the serial port on top of the battery would allow you to monitor/charge each cell individually, but I don't think it's necessary. I think this "top-cover" circuit is able to shunt excessive voltage from each cell to ground, through a resistor, using the integrated circuits. (Message edited by torquehd on September 24, 2017) | ||
| Greg_e |
If it is doing anything, it is doing it at very low currents. probably just trying to even things out between the two packs in parallel. | ||
| Natexlh1000 |
The "101" components are resistors. 100 Ohms. |
