Trek Ride+ Battery Replacement and Performance Analysis

[diablo2112]

I own 2 Trek Ride+ bikes purchased in 2010. Both batteries have since gone bad, and the Trek replacement was ridiculous at over $750 to replace the batteries. As an alternative, I rebuilt the batteries myself, increased the capacity substantially, and used the new build to install additional diagnostics which provide some interesting info the Trek Ride+ system. As the Trek system is proprietary and provided by Bionx, I thought I'd post a bit of info here to document this for future owners.

Battery Replacement

The Ride+ battery in my bikes were based on an 11S4P configuration of Sony 18650 cells. This yields (roughly) a 40.7V pack at 6.7A/Hr or so of capacity. The pack is tightly constructed, and rather than rebuild this configuration to fit in the original case, I went with a custom built pack to fit in my trunk bag. I've built many packs for RC use over the decades, so felt confident in building a pack for the Ride+. I wanted to retain all other aspects of the Ride+, including charger, controller, etc.

I found a decent deal on ebay for 120 18650 Li-Mn cells rated at 2200 mAhr. These cells are labelled as "INR" which I believe is a newer Li-Ni-Co-Mn chemistry. They retain the safety characteristics of traditional Li-Mn cells, while being capable of higher discharge rates (up to 5C). Samsung manufactures these cells, and I suspect these are Samsung cells labelled for off-brand sale. Paid about $190 for a box of new cells. I measured my trunk bag, and felt an 11S10P configuration for these batteries would fit nicely, and give a total capacity (at 40.3v) of 22 Ahr, a nearly factor of 4 increase compared to stock.



To construct this pack, I decided to pickup a cheap CD battery spot welder off ebay. A bit of research, and I found this unit for about $200.



I also ordered a reel of battery tab material. With great care - and I don't recommend anyone try to weld up the following, you will do certain damage if you make even the slightest construction mistake - I welded together the 18650 cells into the 11S10P configuration:



I'm sure more experienced experts here will agree. The amount of energy in this pack is large, and with welding, once you bridge a circuit, the pack is going to discharge until you melt the straps. This is potentially very hazardous. I really don't recommend this to the casual DIYer. There is great risk here, and you must know what you're doing.

With the pack welded, I used fish paper to insulate the vulnerable top and bottom, and the shrunk the whole thing in a large piece of battery shrink wrap and finished construction of the pack:



And now the shrink wrap:


And finished this off with high-current RC connectors



Installation on my Ride+ and Diagnostic Info

Since the pack is now remotely mounted, I took advantage of this to also install a Cycle Analyst meter which can now provide some long-sought info on the proprietary Ride+ performance.

Here's the bike and the meter installed



Note that I swapped the Ride+ components from the original Trek Valencia frame to a Specialized Urban frame, mainly to get a sprung front fork and wider urban tires. I've got about 4000 miles on this frame in riding/commuting over the last few years, I don't commute everyday but frequently enough.

Here's the pack in the trunk bag along with the shunt for the Cycle Analyst:



And here's the analyst mounted on the bike.



The setup works great. I haven't drained the pack or even used a half of its capacity yet. I can report back once I get a much longer ride on the setup. I have monitored performance and found a number of interesting things regarding Ride+ performance.

In the 4 Bionx/Ride+ modes, the maximum current draw is as follows:

Mode 1: ~120W
Mode 2: ~300W
Mode 3: ~550W
Mode 4: ~1200W (!!!!)

Quite a bit more than the rated motor constant-duty power in mode 4. Above about 800W of current draw, my Ride+ motor gives a low humming sound. FYI.

With the system turned on, the steady state power consumption is about 7W (see pic, above). WITH THE BIONX SYSTEM OFF, current draw is in the range of 10mA. I confirmed this by monitoring with the Ride+ controller both connected and disconnected to the Cycle Analyst and the battery. This explains a lot. The BMS on the Trek system has long been suspected of being both a parasitic current draw as well as a terrible BMS. Both my batteries have gone below critical voltage with the Trek system, the BMS may very well be a contributor!

Charging

Charging current from the Trek/Bionx charger is 2A. This charges the pack at around 80W. I'm not sure what it monitors during charge, but as it gets closer to terminal voltage, amperage decreases until the charger cuts off at about a charging current of 0.25A. This is a very good thing for bulk-charge of the LiMN 18650 cells. Individual cell cutoff is ~4.1V/cell, which coupled with the low current tapering gives a margin of safety for the non-balanced, bulk charge. I'm not looking to extract every A-hr from this pack, and prefer a margin of safety, anyway. The stock Trek Ride+ system is bulk charged as well without balancing, so they clearly designed this margin of safety into the system. My pack should be at least as safe, given that I'm charing at well below 0.1C (more like 0.01C at end-of-charge).

The fan on the charger runs at any power draw above 30W. Here's a pic of the Analyst during steady-state charging at 2A:



Excuse the long post, and excuse my return as a newly registered member. I thought I'd document this for others that might be interested in either battery replacement on the Ride+ or some performance details for the system.

 

[exhaustaphobic]

Timely post. The batteries on my 3 year old Ride+ are fading fast and I've been looking for a solution. I called the LBS where I purchased the bike and they told me that not only was the battery "proprietary" and had to be bought from Trek, it would cost me $900!

So, I'm pretty upset.

Didn't know about the parasitic current draw but, if left untouched for some time (days), the bike will "alarm". Took awhile to figure out where the noise was coming from but finally tracked it to the bike in the garage. Never knew what the alarm meant but found that the battery would go flat very quickly when next used.

Also didn't know the BMS was bad, though it seems the batteries should have remained stronger for longer. I'm fairly certain they've not been through 1000 cycles yet.

I love the idea of building my own pack but am fearful of the result.

Thanks for your post. Not sure what to do. This is my commute vehicle. Hate the idea of spending all that money on a battery that will fail in a few years but the alternative is buying another (expensive) bike.

 

[icerider]

Where did you tie into the Bionx system?

Did you open the old battery and just put your new (beautiful) battery in parallel with the Bionx battery.

 

[diablo2112]

Wanted to post an update on my battery pack replacement for the Trek Ride+

I've been using this replacement battery for almost 2 years now with no issue. Range is easily 3x my previous. I also unplug the battery from the whole system when not in use, and this eliminates the parasitic current draw of the Ride+ system, and has preserved this battery quite well.

I constructed this battery without the ability to balance charge (note: the OEM Trek Ride+ battery isn't balanced charged either). Haven't had any problems as a result of this, the battery still nicely charges to 45V and provides nearly the same range as when new. (this is also helped by the 10p configuration, which provides balancing across each set of 10 cells automatically).

I forget to mention how I tied into the Ride+ system in the first place. I opened the OEM battery case (tough job, the battery is literally glued inside the case). Once open, I removed the stock battery. There's 3 connectors: ground, positive, and a temperature probe. I didn't bother with the temperature probe, and soldered 10 guage wire extensions onto the ground and postive leads, brought these 2 cables out through a hole I drilled in the top of the OEM case, and sealed the OEM case back together and replaced it on my bike. I used a standard XT60 RC battery connector here, and that how I tie into my replacement pack, see pictures above.

Hope this helps others with replacement, Trek now wants close to $1000 for a replacement battery, which is ridiculous.

 

[icerider]

I forget to mention how I tied into the Ride+ system in the first place. I opened the OEM battery case (tough job, the battery is literally glued inside the case). Once open, I removed the stock battery. There's 3 connectors: ground, positive, and a temperature probe. I didn't bother with the temperature probe, and soldered 10 guage wire extensions onto the ground and postive leads, brought these 2 cables out through a hole I drilled in the top of the OEM case, and sealed the OEM case back together and replaced it on my bike. I used a standard XT60 RC battery connector here, and that how I tie into my replacement pack

That is exactly what I did with my Trek Valencia+. I added 5Ah of 11s 20c LIPO and more than doubled the range of the aging Trek/Bionx battery. I left the original battery and, if anything, it has gotten a little healthier over the last 12 months, probably from repeated use/recharge in the upper 40% of the charge. I charge through the original Bionx charging port with the Trek/Bionx charger.

 

[Syonyk]

Very cool! Thanks for the update!

If the batteries aren't stone dead, this is probably the best thing to do with a Ride+ pack.

A full rebuild is possible, but it's a royal pain in the ass.

 

[diablo2112]

I also charge via the stock Ride+ battery charger, works fine when you tie the pack into the original battery pack leads. Glad to hear others are having success with a similar retrofit. I'd be a little more wary of a LiPo pack, as they really do need to be balance charged fairly regularly. LiPo has the advantage of lightweight for a given capacity, of course, much lighter than my LiMn pack.

 

[Syonyk]

Have you found your cells to be moderately self balancing as the stock pack is?

 

[icerider]

I'd be a little more wary of a LiPo pack, as they really do need to be balance charged fairly regularly. LiPo has the advantage of lightweight for a given capacity, of course, much lighter than my LiMn pack.

I check the LIPO and balance them once per week using Turnigy DLUX LIPO Battery Cell Display and Balancer (2S~6S) http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=26136

If the inter-cell differences aren't very big, and mine never are, then it takes about 20 minutes per LIPO pack. I have a 5s and a 6s in series. I suspect the small differences I am "balancing out" are actually within the error of the little balancer, but the process is quick and easy and leaves the cells all within 0.02 volts (actual) or so.

 

[diablo2112]

Have you found your cells to be moderately self balancing as the stock pack is?

Yes, I've found the pack to self-balance pretty well. Having 10 cells in parallel helps a lot; no one cell is going to drag the pack down and cause an imbalance.

 

[amberwolf]

That isn't necessarily true; I found dead cells doing exactly that in a Vpower/cammycc pack during a repair (and again, later).

https://endless-sphere.com/forums/viewtopic.php?f=14&t=22750

and I think it was the same in another such pack I repaired but I don't have a handy link.

 

[Ecobykr]

We have a 2010 Trek FX+ that's just been collecting dust for years because the battery died and it was $900 to replace.
NOW I have a new Radrunner with a 48v 13ah battery that I am upgrading to a 52v 20ah battery. I'm going to try to use the Rad 48v 13ah battery I'm removing on the 2010 Trek FX+ to bring it back to life! The original battery was in the 40v range iirc. The new 52v battery comes with a charger - so both the Rad charger and battery can now be used with the old Trek! Any reason why this wouldn't work? I'm excited to get that old Trek back rolling again!