Backup Battery

28 May 2016, 16:36 UTC

I've done it on my E-Go electric skateboard.
Could've added a second battery in parallel for double range,
instead I just rewired so I can unplug from main battery and plug into additional pack with higher AH.

There are way to do it on the OW.

28 May 2016, 17:47 UTC

@thegreck thats true. Usually where I ride my OW to does have a plug in so i just use it there.

30 May 2016, 02:07 UTC

I ride almost exclusively on the beach. No random outlets along the way, thus my desire to develop a backup battery system I made good progress last night. I completely extracted the battery. This thing is well built! My original idea of using the charging port definitely will not work as a connection point for a backup battery. The battery reads 54.4v fully charged. This is baffling, as FM does say it is 48v and charger says 58v. The actual battery pack is composed of 4 12.8v battery packs (16 cells total) in serial which are labeled as being Li Ion (not LiFePo4 as they advertise). Perhaps they are the same thing, I'm not certain, and am just reporting what I see from the inside. Battery pack has a 3rd party part #266504S12 which I googled and came up with nothing. Here is a photo of the battery pack and cable: ![0_1464573825841_100_1894.JPG](Uploading 100%)

30 May 2016, 02:09 UTC

apparently I don't know how to post photos. Any suggestions?

30 May 2016, 02:22 UTC

Until I figure out how to post photos, I am going to make a NiCad battery pack to try as a test plug in backup battery pack. It should cost me below $50, as opposed to buying a $400 LiFePo4 pack only to find my idea does not work. I plan to run a pair of battery cables from inside the battery compartment through a cable gland similar to the one used by FM for the other cables which exit the sealed battery compartment. There is a perfect place for it opposite the location where their cable gland is, where the existing cable exits the battery compartment. From there I will be able to disconnect the stock battery, using the same connector types as they use, and connect my battery pack. IF that works, then I will refine it to perhaps an A/B switch which can switch between the battery packs, and/or ultimately contemplate connecting them both in parallel, making no battery switch necessary. Along the way I will be interested in observing how the iphone app reacts with my new battery connected.

30 May 2016, 02:36 UTC

@Count said in Backup Battery:

The actual battery pack is composed of 4 12.8v battery packs ... labeled as being Li Ion (not LiFePo4 as they advertise). Perhaps they are the same thing, I'm not certain

They are absolutely not the same thing! There are a mulititude of reasons that make LiFePo4 batteries far superior to Lithium Ion batteries, and advertising them as such would be pretty bad. So if these are indeed NOT LiFePo4, you've stumbled upon something pretty big. Are you sure that's what it says?

Just the way they behave -- such as quick charging time, long life (in terms of how many times it can be charged before it starts to lose capacity), they stay cool while charging and discharging, they discharge at an equal rate all the way up until the end of each charge, etc -- make it difficult for me to believe that they're not the battery type Future Motion claims they are.

30 May 2016, 03:06 UTC

All I can tell you is what is on the sticker on the battery pack. The pack is 16- 2.5" green cells, shrink wrapped in a blue wrapping. On the pack is a sticker which reads:

Li Ion Battery
12.8V 6.9Ah 88.32Wh
Part No. 266504S12
Made in China

I will try to remove some of the blue shrink wrap to reveal what is actually written on the individual green cells.

30 May 2016, 03:11 UTC

The individual green cells are double wrapped in reinforced strapping tape, and then blue shrink wrap. I am not willing to dissect the pack further to identify the cells at this stage as I am afraid I may damage it. Perhaps FM monitors these posts and will be willing to respond???

30 May 2016, 03:34 UTC

To upload a photo, upload it to a pic hosting site like photobucket or imgur or imageshack.us and then get the link but use the html code [img]url for pic here[/*img] just dont use the * and that should work

Also if the battery isnt as advertised then this like Greck said is gonna be a huge huge deal.

30 May 2016, 04:18 UTC

I decided to try a YouTube video. It is my first one, so don't critique me! Turn the sound up some... link text

30 May 2016, 09:05 UTC

@count Am i the only one to be amazed that the battery is labelled 12.8v ? can you use a volt meter and check that?

30 May 2016, 16:59 UTC

@Tartopom The output of a fully charged battery reads 54.4v. The only thing I can think is that there are 4 battery modules, connected in series, within the battery pack. 12.8 x 4 = 51.2 volts, which falls between the advertised 48v and what I read, 54.4v. There are certainly some unanswered questions here!

30 May 2016, 17:08 UTC

@Count there is something wrong... because FM claims that the battery is around 116wh and I the sticker it is 83ish...

30 May 2016, 20:52 UTC

@Future-Motion Can you please chime in here? Lithium Ion is very different than Lithium Iron Phosphate, and it's false advertising if the type of battery in the Onewheel isn't what you've been claiming it is.

30 May 2016, 21:08 UTC

Possible explanation,
usually it's 3.7V cells X 3, but they do make 4.2V Li-ion cells.

4.2 X 3 = 12.6V X 4 = 50.4V , upward 54V when fully charged.

31 May 2016, 04:48 UTC

@thegreck - Im very curious to see what comes of this - I've been trying to understand the battery life difference between my two boards. With all other variables remaining constant (tire pressure, rider, route) I have a 10-12% delta on one board. I'm wondering if my 'shorter life' board has an imposter battery. Depending on what we learn from this discussion - I just might have to pull them apart to put eyes on...

31 May 2016, 05:15 UTC

@D-Wave @Future-Motion We hope to get a response quick since rumors(true or not)/reputation consequences might taint the company for a long time.

31 May 2016, 05:32 UTC

@DrN3RD - you're right. I certainly don't want to come across like I'm jumping to conclusions - or bashing FM, that is not my intent. I'm a huge fan and wouldn't give up my boards for anything...however - being a geeky engineering type - this has definitely piqued my curiosity...

31 May 2016, 05:38 UTC

@D-Wave I think I might have found a clue to the battery.

http://www.tradesparq.com/products/578707/4S3P-A123-26650-LiFePO4-battery-pack-12-8V-6-9AH-manufacturers

31 May 2016, 06:06 UTC

@DrN3RD I believe I have fount the battery manufacturer... and although at first glance it portrays itself as li-ion, further reading is indicative of a LiFePo system

http://www.a123systems.com/lithium-ion-cells-26650-cylindrical-cell.htm

31 May 2016, 06:36 UTC

@DrN3RD So after digging some more. I have found these patent related statements

For example, power supply xxx may include sixteen (16) A123 lithium iron phosphate batteries (e.g., size 26650). The batteries of power supply xxx may be arranged in a 16S1P

31 May 2016, 08:36 UTC

@D-Wave Probably the delta come from the fact that the batteries capacity can vary from 6600mah at the lower range to 6900mah for best ones, so I guess it's where the delta come from...

31 May 2016, 17:59 UTC

It does appear as if the term "Lithium Ion" is used to broadly describe several types of batteries, including LiFePo types, from what I read. I am in no way trying to bash or corner FM here by doing what I am doing. I am simply trying to fill a void they have left by not providing the ability to swap batteries. Yes, I realize I am on my own, and have voided my warranty by doing so, but My curiosity got the best of me. What does baffle me is that FM has chosen to NOT chime in and clear up some of these questions, as they have in many other forum posts. I do not think I have uncovered some type of cover up, and lets face it, we ALL would still be riding our OneWheels regardless of the paper specifications. However, some basic answers would be nice???

31 May 2016, 18:13 UTC

@Count I don't think any of us are bashing Future Motion, you've just uncovered something that appears to contradict a very important feature of the board that they advertise on their site. The company seems pretty honest, though, so I'm thinking what you're saying is probably correct, that the label on the battery packs isn't completely accurate.

But I think we'd all like to hear from the company on this issue, just to clear it up.

1 June 2016, 02:32 UTC

@DrN3RD nice digging - looks like a high probability match...and the specs do say LiFePo.
http://www.a123systems.com/lithium-iron-phosphate-battery.htm

1 June 2016, 02:45 UTC

@Tartopom - Thanks - I wasn't aware of the battery capacity range...I didn't see that in the manual - where did you find it?

1 June 2016, 04:46 UTC

@Count We are with you on this one my good sir.

It is not bashing we want, but questions answered. And you have fulfilled many a void. :) My hat goes off to you sir

1 June 2016, 07:52 UTC

@D-Wave it's not in the manual, it's in the specs of the battery pack :) each lipo are not always at their top, so they guarantee a minimal capacity and a generaly observed max one, but we are all the time in the middle.

1 June 2016, 23:51 UTC

Im surprised they still have yet to answer on the battery issue.

3 June 2016, 16:56 UTC

Have you tried contacting them directly? They're probably too busy to read all the forum posts just in case someone wants their input. That's why they have support contacts.

3 June 2016, 18:14 UTC

@badcheese I don't expect them to read all of the forum threads, but you'd think they'd at least read the ones they've been tagged in, which I did. This would be a good fire to put out, pun intended.

3 June 2016, 23:16 UTC

Fire? Problem? I see no issue to address here. The battery works as advertised, correct?

4 June 2016, 02:16 UTC

@Angryviking It's not about how it's been advertised to WORK, it's about what it's been advertised to BE.

There are significant differences between Lithium Ion and Lithium Iron Phosphate batteries (LiFePO4 are non-toxic and non-hazardous, have a lower discharge rate while idle, have a longer life, don't heat up while charging or while in use so are less likely to catch fire, basically just a much more modern energy source), so if the batteries in the Onewheel are not what they're advertised to be, that would be pretty serious. And illegal.

4 June 2016, 17:08 UTC

and with what Greck said, it would be a huge lawsuit to boot due to false advertising.

5 June 2016, 15:55 UTC

Might want to get your facts and terminology straight.

LiFePO4 is a type of lithium ion. The iron/phosphate being the specific ion. The more unstable but powerful batterise people refer to as lithium ion is the LiCoO2. Both contains lithium and an ion. The difference is the type of ion. (Cobalt oxide)

LiFePO4 has 3.65v/cell max charge. 16s battery of the one wheel charges to 16x3.65=58.4v (check your charger)

If it were LiCoO2, max voltage per cell is 4.2v. 16s would yield 67.2v

5 June 2016, 18:32 UTC

@tomtnt Oh man... you're totally right! That's exactly the info we were hoping FM would jump in and give us, so thanks for clearing this up!

I'm no battery expert, and I had been doing all my research on the subject through articles I found with a search for "Lithium Ion vs Lithium Iron Phosphate," and all of these seem to actually be comparing LiCoO2 to LiFePO4 (exactly as you said). But on the Wikipedia page for Lithium iron phosphate battery, it says:

"The lithium iron phosphate a type of rechargeable battery, specifically a lithium-ion battery, which uses LiFePO4 as a cathode material."

And it goes on to say just what you said, that it's more stable and safer than the LiCoO2 battery (which apparently is what most people are referring to when they say "Lithium-ion")

https://en.wikipedia.org/wiki/Lithium_iron_phosphate_battery

5 June 2016, 19:05 UTC

LiFePo4 has a nominal charge of 3.2V, which is lower than the other Lithium batteries.
4x 3.2 = 12.8 V, so if it's 4 cells and labeled 12.8 V, then it's a LiFePo4.
And you always charge batteries with a higher voltage than their nominal voltage.

30 June 2016, 06:42 UTC

@Count Did you try to assemble the OW again to see if it works? Or need to recalibrate or something like that?