How to replace a discontinued battery?

JessePhillips

New Member
I'm new to this forum. I've searched on here a bit, but didn't find a great direct answer to my question (fogive me if this is redundant).

I just got my first ebike for FREE (ProdecoTech Stride 400) with a busted battery, that has been discontinued! The prev. owner gave me a phone number to a bike-shop that says they can fix it. I'm wondering what my options are for fixing it myself or replacing it with a non-oem battery (one that won't fit the special rack & plug-in).

Has anyone replaced a battery that was discontinued? Either by fixing it themselves? Finding someone to do it? Or getting a whole new battery and hacking the bike to work with it?

I would LOVE if I could buy a battery (with charger and rack) that I could easily splice to my bike. But the Hall Controller is in a part of the bike that seems tied to the OEM battery (see pic)

IMG_7879 2.jpg

Ok, so I have read on here that Hi-C is a good company to replace my battery. It seems a simple solution is to send the original battery housing to someone who will replace the cells. I don't have a price on this yet. I've even found a guy on Etsy (Raymond Yu in California) that says he'll do a custom ebike battery for $280. Sounds very cheap, and seems a bit fly-by-night as he was going to ship the battery via USPS (that's illegal, right?) - but I don't have quotes yet on battery fixing.

Another option seems to replace the cells myself. which I've also read on here (or elsewhere?) that it's difficult, and you even need expensive equipment (apparently you shouldn't older lithium ion batteries, only spot weld them), and not that much less expensive than buying a new battery (which doesn't work in my case, of course). Seeing that it's difficult, dangerous, expensive etc, I don't think I'll try this one.

My favorite option would be to hack my bike so that I can buy a cheap generic battery and figure-out how to plug-it to the controller and whatever else, and then weather proof the new connections. I would love to learn more about how to do that, since it sounds fun, and it would be easy to replace the battery again in a few years, and it seems to be the cheapest route. Although I'd need to learn how to do this sort of thing. I have to believe that many people have done this sort of thing by now, even several contributors here, but I couldn't find a guide for this kind of work. Reading comments, I can tell that some of you know how to do this. I hope you read this. We should develop a guide so more people can solve this kind of problem.
 

Dewey

Well-Known Member
You're a braver man than me for sure, I'm not an electrician and would be afraid of making an error that would cause the battery to malfunction or worse. On this site Court has mentioned a company in Nevada that rebuilds batteries. I gather the biggest issue with rebuilding packs is if the BMS still works. Endless Sphere is the best forum for asking questions from folks that love to do this sort of technical work.
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Getting around that OEM battery connector isn't that big a deal for most DIY'ers. It easy to figure out which is positive and negative just using a volt meter. Once that is done it's just a matter of making an extension long enough so that it will work out for the new battery. The XT60 and XT90 connectors will work well for your purposes, are inexpensive, and are easy to source. If you can solder (or know somebody that can), this should be an easy project.

Shipping LiPo's is legal for those with a permit to do that.
 

JessePhillips

New Member
@AHicks Ah! I see. So I could simply connect a new generic battery to the old OEM plug? So this way I obviously wouldn't have to move the Hall Controller out of that box, correct? The only problem then is it feels a bit hacky to have a cord running from that old plug to a new battery.

Are there any common ways people use to protect that connection from the elements? Do you know anywhere I could find pictures or diagrams of folks who have done this?

Thanks so much for your help!
 

JessePhillips

New Member
@AHicks One more question: must my replacement battery match the old one in volts and Ah? That is: if the replacement battery has different specs, will it mess-up my controller or something else on my bike that was expecting the old specs? know what I mean? Or is a battery generally a "black box" distinct from the rest of bike electronics, thus I could use a 48v, 20Ah battery just as easily as a 36v 10Ah battery? (the rear wheel hub motor on my bike is 400W I believe)
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Jess, to the best of my knowledge staying with the 36v battery might be the better plan. There are later model motors and controllers that would be safe going from 36 to 48v, but the minute I tell you that would be something worth considering, yours will be one that will choke on the higher voltage. Letting the smoke out of anything like that may get expensive. Not worth the chance....

Ah are a different story. You can do whatever you want there. I would just caution that there are no free rides. Higher Ah batteries are heavier. Get what you need to get the job done to keep the price AND the weight down. -Al
 

harryS

Well-Known Member
Couldn't see nothing on your photo. This is clearer. You can open the box that contains the controller, find the two wires that go to those prongs, cut them off the prongs and wire in a battery cable with a connector. If you leave the prongs attached, they need to be covered or they could short circuit your new battery if any metal contacts them.

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Best to stay with a 36V battery if you had that now A 36V10AH is common. Probably get you 20+ miles if you ride 12-14 mph.

Buy a battery with a mounting cradle. It will have about six inches of cable on the cradle. Sometimes they will mount a connector for you. Your bike isn't going to draw enough current that a 12 inch line between controller and battery will cause a power loss, but I would use 14G silicone wire.
 

JessePhillips

New Member
Update: @harryS @AHicks
- Prodecotech is not getting back to me, they are no help.

- FTHPower.com said they can't do it because this battery sends a proprietary signal "dataline" to the controller and the controller can't work without that proprietary signal. They also said that their batteries won't work on my bike, for that same signal reason.

- This guy on Etsy says he can do it for $280 + $25 shipping. Seems shady.

- Hi-C in Denver says they can do it: $479 + $40 shipping - and they seem to be confident than can deal with the proprietary signal issue.

- Battery is currently at a local shop (GForce near Atlanta, GA where I live), waiting to hear back an estimate.

- After watching more battery videos, I'm wondering if I could replace the cells myself. Perhaps it's worth a try before spending $520+ ? This video was encouraging, that I could mayyyyyyybe replace them myself with soldering:
Folks on this forum say soldering should not be done on L-Ion batteries because the heat could make them explode, that spot welding is what's needed (and spot welding equipment is $200+) - however this youtuber does it and warns it can harm the battery health.

- Watching this video on the Vruzend diy battery kit very much encouraged me that I could someday build a battery, if I needed to. I'm wondering about doing this for my son's powerwheels
 

harryS

Well-Known Member
Maybe check with these guys, although I'm dubious about being able to legally ship a battery to them via ground transport. They are in Las Vegas.

 

JessePhillips

New Member
@harryS thanks! I've seen that Las Vegas company on here, but it also seems shady. Some posts on here were somewhat discouraging about them, but I guess I might as well find out their price. Thanks for the link!!! Harry, thank you for your help, you are a rockstar. Thank you to everyone on this forum who has taken the time to help me out!!
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Maybe it goes without saying, but when you talk to them, make sure you ask about the freight to get your battery to them. Wondering if they might be able to ship you a box/package that could be used to send them your battery leagally, or even advice on how others have sent them batteries (legally).
 

harryS

Well-Known Member
Soldering 18650 cells is no fun. I've done like four cells. I couldn't imagine doing 52. Soldering to the nickel strips on scavenged cells is much easier, but now you're dealing with second hand cells. Unless one is going to build two or more batteries, the cost of a spot welder is hard to amortize.

I would think FTH power knows what they are talking about the battery-to-controller security , but I wonder why Prodeco would want the expense of chipped batteries. You might look at the controller and see if they only run two wires from those three battery prongs to the controller. Another option is to replace the controller/display. Prices for the pair are $60-100.

Easier to replace a controller than build a battery.
 

JessePhillips

New Member
@AHicks @harryS Thanks for the tips!

@harryS - good insight!
1) So what if they do only run two wires from those three battery prongs to the controller? What will that imply? Thanks!

2) That seems reasonable on the controller/display. Where would you buy a controller/display? And if I went that route, where would you buy a battery? FTH?

Thanks again!!!
 

AHicks

Well-Known Member
Region
USA
City
Snow Bird - Summer S.E. Michigan, Winter Gulf Coast North Central Fl.
Another point about batteries, especially using cells from separate sources, is how well individual cells match each other on voltage. Top shelf battery packs will come with cells that match VERY closely and will outperform packs with cells that aren't matched (like those you might get at random when ordering on the open market) pretty easily. Point being, NOT a fan of the idea of building a battery with as many cells as we are talking about here. Building a pack with 2-4 cells is a different ball game. -Al
 

harryS

Well-Known Member
So what if they do only run two wires from those three battery prongs to the controller? What will that imply? Thanks!

Thanks again!!!

Means FTH is wrong. Two wires is positive and ground.

Now if there were a third wire, maybe there's some simple scheme to tell the controller "I'm an official Prodeco battery". It could just be a resistor in the battery, or a signal voltage.