Added a 2nd integrated battery to my Luna Z1: 48V, (17.5ah) + (17.5ah) = 35ah!

[Tom@WashDC]

A while back I decided I wanted to carry a 2nd OEM battery to swap when my primary ran low. A new battery costs about $415. I formed a battery cradle to fit at the bottom of the downtube made from solid rubber.

Then I figured that since I had a perfectly good Hailong battery lying around that I wasn't using, maybe I could use the battery pack instead of spending $425. I could install a Battery Balancer ($48) and run both batteries at the same time. So I removed the battery pack from the Hailong case, soldered in a different charging fitting, soldered an XT60 connector for the main power, and wrapped the pack in black Gorilla tape, with a layer of high density foam on the one side of the battery that will rest on the downtube.

Then I installed the Battery Balancer/Connector inside the frame in the motor cavity, running a connecting wire with an XT60 connector to connect the 2nd battery.

Secured the battery with rubberized velcro straps. It works like a charm. I actually have more available power on demand, and 35amp hours! Incredible range.

 

[juggernaut]

I’m guessing the Hailong battery case didn’t fit in the frame for a neater look?

 

[Tom@WashDC]

I’m guessing the Hailong battery case didn’t fit in the frame for a neater look?

Correct. The Hailong case would hit the upper shock mount. With The bare battery pack I had only 1/2 clearance on the shock mount. I can make a nice case out of Kydex, or use a 3D printer, which I may do in the future. The OEM battery fit perfectly in the cradle, and looked clean, but for now I figured why not use my perfectly good Hailong battery that was going to waste.

 

[juggernaut]

For sure. I can’t imagine there would be much range on a single 17.5a/h battery with the Ultra motor.

I should receive my Frey Beast next week which comes with a 24.5a/h 60 volt battery. Hopefully it has reasonable range.

 

[Tom@WashDC]

For sure. I can’t imagine there would be much range on a single 17.5a/h battery with the Ultra motor.

I should receive my Frey Beast next week which comes with a 24.5a/h 60 volt battery. Hopefully it has reasonable range.

For sure, 24.5ah is a huge amount, you will have great range, and you will love it. The 17.5ah was good range if I ride casually with my wife. I could squeeze 35-40 miles on it riding on paved trails. On the other hand when I ride really hard and agressive, 25 miles was my max range. My riding buddy has a Sonders Rockstar with with a 21ah battery which meant I was the one causing our rides to end early. Not anymore.

 

[Gionnirocket]

I had a real tough time finding a battery in my tight triangle.
I ended up with this...

Frame Bags for Battery and Wire Management.

I don't think I've stumbled on anything novel here.... but I haven't seen anything posted taking this approach. Recently I purchased a smaller battery that would fit in my very tight triangle and I needed a way to secure it and make it somewhat presentable. That along with following some of...

electricbikereview.com

I fabricated an aluminum L bracket to bolt to the bottle bolt holes and secured a heat shrink battery and then found a suitable bag to cover and add additional support
If I were you I would shrink wrap the battery as duct tape has too much give, especially in the summer heat to hold things firmly in place.

 

[Tom@WashDC]

I had a real tough time finding a battery in my tight triangle.
I ended up with this...

Frame Bags for Battery and Wire Management.

I don't think I've stumbled on anything novel here.... but I haven't seen anything posted taking this approach. Recently I purchased a smaller battery that would fit in my very tight triangle and I needed a way to secure it and make it somewhat presentable. That along with following some of...

electricbikereview.com

I fabricated an aluminum L bracket to bolt to the bottle bolt holes and secured a heat shrink battery and then found a suitable bag to cover and add additional support
If I were you I would shrink wrap the battery as duct tape has too much give, especially in the summer heat to hold things firmly in place.

That's a nice setup, and 10 extra AH is good, that's all I really need for practical purposes. This is just experimental stage. I really wanted to try out a battery balancer rather than fix a swappable OEM battery on the downtube. Now that I've experienced the extra "umph", for certain I will install a nicer, more fitted arrangement. But for now, it's "over the river and through the woods" with miles and miles to go!

 

[greeno]

When I first got into e bikes some years back I started with a BBSHD and a 14ahr battery.
After running out of juice a few times and having to pay the piper for that I decided on making my own.
Found a guy that makes good quality bags that I use for all the battery's I build for myself and friends and they work out really great.

Caring a "spare" in my backpack wasn't really an option as the pack weighs in at like 16lbs with a full bladder and all the shite I bring with me.

And believe me that pack has saved my ass a few times in the outback.

So finding a bike that was conducive to being able to securely carry a larger battery was my first priority.
First thing I did was figure out the LARGEST battery I could fit, which was ironically 34.5ahrs/16lbs ( 10x14 ) .
But after using that battery for a bit and usually coming home with 52v or so I decided to make a smaller one which ended up being 24ahrs/12lbs ( 7x14 ).
I designed it in such a way as to be able to add another group in parallel to give me 27.5ahrs if needed without tearing it apart.

I'm actually thinking of making up a 21ahr battery to save a bit of weight and might go with a 48v pack to save even more weight.

I have always ran a 52v system and it would be nice to have a 48v battery to side by side compare the two.

More range is more important to me than power.

Bike with the smaller battery comes in around 60lbs

Smaller 24ahr pack with my Fox 36.

Larger 34ahr pack with a Wren Inverted fork.

 

[Tom@WashDC]

Update on my original post up top: Battery connector is working perfectly, and having this much power at my disposal has really been a game changer. Don't know how I lived with a 17.5Ah battery. The connector seems to sip current from both batteries efficiently. I can run this bike a lot harder, for a lot longer. No need to conserve power, and I have plenty of juice on my way back home with no noticeable voltage sag. The rubber coated velcro straps hold the battery with no problem.
35Ah is the way to go!

 

[Tom@WashDC]

I’m guessing the Hailong battery case didn’t fit in the frame for a neater look?

I had other options which included using the bottle bosses to hold a conventional battery, or a second OEM battery, but I decided that I do not trust the bottle bosses imbedded in the CF frame to be as durable as those in an aluminum frame, especially when I wipe out. I figure the lateral forces may rip the bottle bosses out of the downtube.

 

[Tom@WashDC]

Update to my Dual Battery Connector Install. See original post of July 7 2023.
The Battery Connector is working flawlessly connected to two 48V, 17.5Ah batteries. I rode it for about 30 miles on the hottest day (98 degrees) this summer and measured the ambient temperature inside the frame right where the unit was positioned. The air temp got up to about 120 degrees after the ride was finished. The CF frame has never felt warm to the touch where the unit is positioned. I have more than enough "juice" when I'm riding, and have never experienced any more voltage sag. I am very pleased with results.

The Gorilla tape wrapped battery resting on the downtube is very secure. I've eliminated two of the velcro straps as there are fewer lateral forces on the battery than I anticipated. The underside foam layer barrier of the battery has molded around the downtube, adding additional grip.