Help/suggestions for DIY replacement battery for discontinued IZIP ZUMA

[crazyjaw]

So, sorta on a whim i swiped up a 250$ 2015 e3 zuma from facebook marketplace. It's in excellent shape, and has never been ridden... namely because the battery is dead and the charger is missing (the guy gave me his purchase agreement from REI, and the battery was at 10 volts, 4 years ago, so i imagine super dead).

Looking for replacement batteries online, and they seem to go for at least 400$! (i assume this is in part because its a discontinued model).

So i could go down that route... but it seems like all i really need is to replace the cells, the whole rest of the battery (should) be good. So i just wanted a sanity check for you fine knowledgeable folk, would it be reasonable to open up the battery, desolder all the cells, and replace them with newer (potentially higher capacity) versions of 18650. For what it's worth it was a 36v 12ah originally.

Im generally technically competent, and have done a ton of low voltage projects, but this would be my first thing of this high power motor class (and im kinda excited to learn about it).

 

[Ian Moone]

Have you Contacted the manufacturer for a replacement pack yet ?

 

[crazyjaw]

yeah they said they dont do this battery anymore, and referenced me to a battery repair joint. I asked him about swapping out the cells myself and said yeah that's what the repair joint would do so i could go for it (in taht sorta shruggy, "hey you be you, this is out of warranty anyway" sort of way).

Still i was hoping someone here has done something similar, and had some tips or warnings. Particularly if there is a good place to get good/reasonably cheap cells.

 

[indianajo]

See this thread about repair centers: https://electricbikereview.com/forums/threads/ebike-battery-replacement-repair-service.26997/unread
You have to drive your battery to the center, you are not allowed to ship it.
Adjacent to that thread is one about batteries in general. One or two guys have repacked the battery. Getting it to hold together under the stress of potholes is another level of skill.
I'm pretty handy, but I'm not bold enough to weld together bottles that if you penetrate the metal with too much energy, bursts into flame. Flame about a foot in diameter if watching cell phone batteries on television is any indication. My welding gloves wouldn't hold that flame off I don't believe.
Plus the new cells you can buy, there aren't a lot of reputable vendors.
If you live in ***** you might be able to find the source of genuine new cells. If you live in N. America, the best I think you can do is buy a new battery from a reputable vendor and adapt the connectors and wiring.
I bought two **** batteries from amazon & ebay, so the one generic battery vendor I can recommend from experience in USA is luna.
People say a lot of nice things about grin technology in Ca.
I've seen one MTB conversion at the local grocery, the guy said he had soldered his battery together from cells he bought on ali. I've never seen him or his bike again.
You will see on my bike left, I wrapped a generic luna battery in aluminum angle, some plastic insulation, a PVC sheet for rain resistance, than hung it on front of my bicycle. That bike shows up at the grocery 2 or 3 times a week where the guy who built his own battery does not park.

 

[crazyjaw]

hmm i dont actually have a car so my ability to transport the battery is limited (but i will call around to see if there is any place close and cheap).

I have soldered a few dozen of those 18650 cells for various projects over the years (though in small 1-4 unit packs). _welding_ them with a proper welding kit seems like it would throw way to much heat at it (and i;d also be scared).

Thanks for the tip on battery vendors. Getting decent batteries is my biggest concern if i do it myself. My current plan is to call around and see if there is a shop here in SF that will do it on the cheap, otherwise ill roll the dice.

 

[harryS]

Is it this battery? Being Held by the owner of this website.



I guess you cannot support the seat without the battery in place? If you could, it would be easiest to buy a downtube battery and clamp it to the frame. If the cells are easily removed from that case, you might entertain that alternative,

There's no soldering of the cells. They're spot welded into an array. Soldering is actually worse for them. as it's hard to do w/o getting them too hot. They have little spot welders for batteries. Cost you about $200. Add $160-200 for cells. It's not worth doing this yourself.

With your 2 cell and 4 cell battery projects. you may not have come across the Battery Management (BMS) cards. They isolate the terminals of the internal cells from the outside world when they detect a voltage problem.

Your 48V battery will be made up of 13 groups of cells in parallel. Probably 13x3 or 13x4. If you open the pack, you'll see the cell array, the BMS card, and a whole bunch of wires. That whole array could be dead, or it might have as much as 40 volts in it. You can't tell what's in those cells since the BMS has shut down the pack. That's why you have to be very careful if you open it.


If you want more direction ask the folks at endless-sphere forums. They will tell you to carefully open your pack, determine how the 13 series groups are arranged in it, and to report the voltage on all 13 groups. The results will tell whether the cropus are still usable, and if you have any options.

 

[crazyjaw]

naw its this bikehttps://www.rei.com/product/852082/izip-izip-e3-zuma-lsf-bike-2013 with a horizontal rack mounted 36v battery (so likely 10 groups of 6).

Looking more at the alibaba costs for the individual cells, they are more expensive than i thought (at least if you get the high quality/consistent panasonic ones), which puts it more in line with the refurbishment costs ive seen a few places. However i'd have to find a hazmat shipper in my area to get access to them.

There is also the option of using one of these bottle batties like https://lunacycle.com/36v-ebike-battery/ or a generic rack mounted one https://www.amazon.com/Ebike-Batter...y&qid=1556332273&s=gateway&sr=8-19&th=1&psc=1. It seems like they'd just wire easily into the controller (assuming it doesn't expect something weird and proprietary from their BMS). However i dont think theyd fit in the somewhat weird rack well and id have have to just crudely jam it on there somehow. I am now thinking ill try the refurbishment if i can, else just do a generic pack.

 

[indianajo]

If you live in Hawthorne you might have a concrete shop area with concrete floor & metal roof. If you live in SF I suspect you live in a highly flammable apartment. If you, rebuilding a battery, set fire to your apartment, your neighbors landlord and their lawyers will take every dollar you own and every doller you could earn in your lifetime, too.
I don't even weld in my cinder block garage with the concrete floor. It has a wood roof. I weld outside. I charge the battery out there also.

 

[tomjasz]

I am now thinking ill try the refurbishment if i can, else just do a generic pack.

I am now thinking ill try the refurbishment if i can, else just do a generic pack.

there should be no,problem finding the same battery. Guaranteed they didn’t use a custom case. Take some pictures of all 4 sides, the connectors, and measurements in nearest MM. I’ll help you find a replacement. Note, help find I’m not hunting a sale. Given the likely low power demand you don’t need the latest and greatest cells. PF cells are a good choice.

they seem to go for at least 400$!

No surprise, actually a good price if brand name original cells. That case is nothing special. Availability shouldn’t be a problem

i'd have to find a hazmat shipper in my area to get access to them.

thats not you’re responsibility. Shipper handles. Sounds like the problem is battery sticker shock. I’ve been working with the Chinese factory building RAD batteries. Careful on Aliexpress. It’s the WORST place to buy individual cells!

There is also the option of using one of these bottle batties like https://lunacycle.com/36v-ebike-battery/

useless warranty. Is this it? https://www.monsterscooterparts.com/36v-12ah-li-ion-battery-pack-izip-zuma.html

In my opinion one of the best deals and a Bluetooth BMS. You could top mount on the rack. I’ve started using these cases and soft pack batteries.

 

[harryS]

Nice welded-on luggage rack on that bike. Probably could carry a rider. You got Thomas to help. He'll find you a pack that's safe.

 

[crazyjaw]

Thanks so much for the advice.

Yep thats the battery. The i busted out my calipers and got ~ 155mm x 73mm for width and height (cant find my bloody tape measure for the length). The case of the battery has these little slots in the side (tried to get it shown in the photos, but came out poorly). Those slots slip into two welded bars on each side of the batter, which makes the width of the racks bed smaller (~ 148 mm). The connection to the controller is obscured (since they are flush with each other). I havent taken the battery out yet, since its not clear how to remove those little pins on the top without damaging them. The charge connector is a 4 pin XLR

I did have a bit of price shock initially. Mostly because i had bought cheap batteries in the past, so it seemed like the price was way more than materials. But i had bought crappy bats whose capacity was suspect. "good" cells tend to be at least 3 or 4 bucks in bulk, which already puts it in that 300$ price range. So yeah now my expectations are properly aligned with reality .

Also you guys are really active for such an esoteric board, i really thought i would have to wait days for a reply.

 

[tomjasz]

really thought i would have to wait days for a reply.

Pretty cool forum. More adults than usual, IME.

What is the name in the plastic? Lower res picture and old eyes keep me from reading...
EDIT, oops it says charger. Any other markings?

I’d bet the case is either from http://en.kssssj.cn/index.html?fbclid=IwAR0UmRTdCNA_1Q9P_gol5DCs5m06QBWqYgdcOutW2LXxMWvEfGTY-K9j1Ms

Or, http://www.reention.com/

Once identified there are a number of good sources direct from China. Sources I’ve known to be reliable. When ordering a battery I ALWAYS INSIST ON A SPARE BMS. They are cheap and the most common failure.
I paid $12 for the last spare.

 

[harryS]

Charger.

 

[tomjasz]

Charger.

???

 

[crazyjaw]

Good eye, it looks like it's this guy: http://en.kssssj.cn/products_detail/productId=251.html. What are my next steps?

 

[tomjasz]

Good eye, it looks like it's this guy: http://en.kssssj.cn/products_detail/productId=251.html. What are my next steps?

Confirm it is. Then which cells? I’ll Skype my contacts and have them connect with you. Mind, i’m Not making a sale, just a help finding a reliable source. Message me with email using the conversation function here.

 

[crazyjaw]

Hmm it looks like i "cant start a converstation with this user" (and i am also restricted from viewing your profile for some reason, though i can view others). Is there some privacy setting im hitting up against?

And just so i'm clear about the current plan, im going to order the 36v battery pack, and BMS separately through your contacts and assemble them myself using the case i current have?

 

[Ian Moone]

Hmm it looks like i "cant start a converstation with this user" (and i am also restricted from viewing your profile for some reason, though i can view others). Is there some privacy setting im hitting up against?

And just so i'm clear about the current plan, im going to order the 36v battery pack, and BMS separately through your contacts and assemble them myself using the case i current have?

There Might be a site restriction since you're a New member, not sure .

 

[tomjasz]

36v battery pack, and BMS separately through your contacts and assemble them myself using the case i current have?

The best choice would be EM3ev.com
The delivered cost would be around $400. Put your choice in the cart and calculate shipping and fees.
https://em3ev.com/shop/36v-super-shark-ebike-battery/?currency=USD

 

[Ian Moone]

Thanks for posting the Link Tom ! I'm also looking to Rebuild my 36volt/ 10Ah pack for my EG Bali 350 ?