14.5ah vs 17.5ah?

[330rcs]

I bought the ultra eagle and got the stock 14.5ah battery and now I'm wondering if I should have gone with the 17.5ah. I wasn't sure if the 3ah difference would be worth the price difference so I didn't get it. I have a rear hub bike as well with a 52v 19.2ah and I can definately go further and ride longer it's been perfect for my needs going to be almost 2 years soon and I never ran out of battery power riding my rear hub whereas under 2 months of having the eagle I have ran out of power a couple times. I was always within a mile or so of home so I am thinking maybe even if I had an extra 3ah for my needs it would probably be just enough.

Is the price difference between the 14.5ah and 17.5ah worth it for the extra 3ah?

 

[Sierratim]

The difference works out to an extra 20% capacity if you use 100% of the rated battery capacity. It's more like an extra 24% capacity if you use your battery more conservatively to extend its life (keeping the charge between 20% & 80% helps a lot).

I personally like more battery capacity with mine being right at 17Ah. Even then, I carry a backup battery for longer rides just to be sure I don't walk home. Can't say if it's worth the extra $ to you but a second battery for $400 seems reasonable to me. YRMV.

 

[Deafcat]

I pretty much always go with the biggest main battery I can fit nowadays. Reason being, the weight gain is minimal, and the FUN gain outweighs the cost difference.

Bigger battery pack keeps the voltage up longer through the day, and delays the eventual drop in top speed and assist wattage. Similar reasons to use 52V over 48V packs...

Finally, and maybe most importantly by many folks standards: With a bigger battery, you're less likely to drain the battery completely, which will usually make the pack last longer, preserving the investment.

 

[greeno]

I have a friend who has a Juggernaut Ultra FS and he ordered the bike with a 48v 21ahr battery that he has never used ( we build our own battery's ). He is in SD Cal and he is asking $350 for it. Don't know if the mount is the same on your bike or if you would want a 48v battery? Let me know might save you some cash.

 

[330rcs]

I have a friend who has a Juggernaut Ultra FS and he ordered the bike with a 48v 21ahr battery that he has never used ( we build our own battery's ). He is in SD Cal and he is asking $350 for it. Don't know if the mount is the same on your bike or if you would want a 48v battery? Let me know might save you some cash.

Appreciate the offer but I need a 52v and the issue is due to the frame it's not able to fit their 21ah battery the highest is 17.5 and the owner said the mount may still need to be moved it will still be a tight fit

 

[greeno]

No worry good luck.

 

[ElevenAD]

imo even 17.5 is to small for an Ultra, get the biggest pack available!

 

[330rcs]

imo even 17.5 is to small for an Ultra, get the biggest pack available!

Unfortunately the 21ah doesn't fit the medium frame of the ultra which is what I have. Roshan said even the 17.5 is a tight fit and I may have to adjust my mounting plate.

The good news I decided to get the battery at the perfect time. I ordered the 17.5ah at 25% off for black Friday sale! Awesome deal.

 

[330rcs]

EM3ev 52V (14S5P) Jumbo Shark Ebike Battery | EM3ev

em3ev.com

There's 52V 21Ah available, I don't know if it will fit though.

328.68US $ 30% OFF|Original 48v 20ah Battery 52v Ebike Battery Polly Dp-9 Downtube 40a Bms 350w 500w 750w 1000w 1500w 18650 Cell Bbs02 Bbs03 Bbshd - Electric Bicycle Battery - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

365.99US $ |Ebike battery 36V 48V 52V Hailong Shark Powerful 18650 Samsung 35E Electric Bike Batteries For 1000W 750W 500W Motor Kit akku|Electric Bicycle Battery| - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

312.67US $ |Ebike 18650 Lifepo4 Battery Pack Bafang 48v 17.5ah 52v 36v Volt Li-ion Bateria Lithium Batterie 21700 Electrical Bicycle Battery - Electric Bicycle Battery - AliExpress

Smarter Shopping, Better Living! Aliexpress.com

www.aliexpress.com

I don't see a 21ah anywhere in those links but yes it really doubtful it will fit the medium frame. I have been checking and measuring and even the 17.5ah is a tight fit. Honestly even when I took out my 14.5ah to measure it takes quite some messing with it to even get it back in

 

[330rcs]

Some pics of my medium frame and measurements with the 14.5ah battery. The issue is at the top part of the frame it starts to narrow significantly. If the 17.5ah fits then I will have to even remove my triangle bag, it won't fit with it. Even Biktrix support and Roshan weren't sure if the 17.5ah will fit. I'm taking a chance if it doesn't fit I have to pay return shipping to send it back. Maybe they will charge me a restocking fee as well.

 

[330rcs]

Perhaps that's why Frey and WattWagons have dual battery option for Ultra powered ebike?

Biktrix Ultra Beast has dual battery though.

Are they 48v or 52v? Luckily I have a second bike otherwise this 14.5ah would really suck and already has me considering other options for the future. For my next purchase I should realy be sure on the batteries that can fit the frame before making my purchase. I'd really want 21ah next time. My rear hub bike has a 52v 19.2ah and it's been perfect for me. I have never ran out of power riding my bike and I can have all the fun I want and get super tired and come back with a few bars remaining. On the ultra I have already ran out of power a few times and had to walk my bike back.

It doesn't help that I hate the battery meter on this bafang version. It's not accurate the percentage is BS it will just dump when it comes down to 20-30% and people told me to go by the voltage and not percentage and even that sucks because the voltage is always jumping around while you're riding so I'm just always guessing where my battery life is at.

On the 750w rear hub bafang that battery meter on the old small lcd is way more accurate. I go by the bars and it always stays stable. When it comes down to 2-3 bars it never just all of a a sudden dumps it's always been accurate. I know by 3-4 bars it's time to come back and I've never ran out of power going by the battery meter.

Check out this freaking thing The Scout they give you an option for a 35ah battery! Though it's not hard case it's a frame bag there's no pic of it. That's way more than what I would need though. I would be too tired to go that long. I think 21ah would be perfect.

 

[330rcs]

When you go to those AliExpress link that I provided, you can select different batteries (voltage and capacity)
There are 52V 21Ah batteries.

But if it doesn't fit, never mind.

OK yes I see them. It's worth checking into I was speaking to an aliexpress vendor as well but their 21ah battery was too big. In one of your links its a little smaller. Appreciate it.

 

[330rcs]

If you're talking about the last link, I don't think the battery will be smaller.
They use the same picture for all batteries, but they provide this info when you scroll down.

So yeah that's basically the issue. I was considering to buy it from aliexpress the 52v 17.5ah because it was only $423 for Panasonic or Samsung cells. Theirs was 370mm x 90mm x 110mm. The Biktrix 17.5ah is $800. Though I would have had to switch out the battery mount as well if I got the aliexpress battery. The Biktrix battery is 360mm x 90mm x 110mm so to not take a chance I would had to go with Biktrix because it's the shortest that I could find in 17.5ah. Luckily I got the black Friday discount and saved $200. I spent $664 I believe but, at least I don't have to change out the battery plate and I have the best chance at it fitting. All these things I should have definately considered before making my purchase but if it does fit will be awesome I think it could be just enough power for my needs.

 

[tomjasz]

52V, 14 cells in series, is a poor fit in a Hailong Shark Pack. Cells will be glued together without any separation. EM3ev uses Reention cases. See their webpage for details.

 

[330rcs]

Incredibly fast shipping by Biktrix I already received my 17.5ah battery just now and it worked it fits!! Just barely. I don't think there's anyway a 21ah can fit or anything larger than this. Even my triangle bag still fits. You can see where the battery curves how narrow the space is between the battery and the frame. I have to say that even during the pandemic and holidays Biktrix still manages incredible shipping speeds. I remember being impressed when my ultra eagle also arrived within few days.

 

[Deafcat]

Right on, I use 52v 17.5ah as well, it's plenty of range for me. I don't notice any drop in max power output until past the 40km range mark, which basically means I can do 2 days commute both ways on the same charge comfortably (which means, if I forget to charge on a given day, I don't have anything to worry about, commute-wise). I could in fact drag that out for a third day of riding, but with some loss in top speed (I don't like that!).

 

[ExPatBrit]

No worry good luck.

If you still have that 21 Ah re-ention dorado battery message me I am in seattle

 

[burlguy]

I have a friend who has a Juggernaut Ultra FS and he ordered the bike with a 48v 21ahr battery that he has never used ( we build our own battery's ). He is in SD Cal and he is asking $350 for it. Don't know if the mount is the same on your bike or if you would want a 48v battery? Let me know might save you some cash.

If your friend still has the battery I would like to know more and have paypal on standbye.

 

[tomjasz]

If your friend still has the battery I would like to know more and have paypal on standbye.

Read carefully, “we build our own battery's”.

Rethink spending your dollars on amateur builds. It may not be as good a deal as it appears. I’d be asking if the seller has a hazmat shipping account and for far more details on the battery. Beware.

 

[330rcs]

I am selling my 52v 14.5ah Biktrix downtube battery compatible with Ultra Eagle and Duo if anybody is interested message me.