Posts: 1
Joined: Sun Mar 13, 2022 1:03 am

Re: i3 HV Battery Upgrade

I would be interested in any upgrade seeing as my warranty will expire in June of this year and I'm not below the 70% threshold for replacement.
Posts: 1
Joined: Thu Apr 21, 2022 4:45 am

Re: i3 HV Battery Upgrade

Can I offer an alternate product suggestion?

The i3 platform has a reasonably large amount of space allocated for the REX engine/generator unit. On BEV i3s, that space is simply empty. The worst kind of empty too, because BMW didn't even let you use it for storage - it's just open space underneath the car.

If you could manufacture a supplementary battery that fits in that space, which works in conjunction with a factory battery to increase the range, you'd really be on to something. It'd be smaller, take fewer cells, and be more widely applicable than an entire main battery replacement.

An electrically different option could be a battery-based pseudo-REX - a drop-in replacement battery pack that pretends to be a REX to fool the computer. Then anyone who has a REX engine failure, or who just wants to change to a BEV, could remove the gas engine, install the new battery unit in its place, and enjoy a few extra miles of all-electric range. The car would just think it still has the REX, and switch it "on" when the main battery pack was low.
Posts: 1
Joined: Thu Aug 25, 2022 3:01 am

Re: i3 HV Battery Upgrade

I hope that more 3rd-party battery pack builders start producing replacement packs for the i3 and other EV's as has happened with some gasoline-electric hybrid vehicles. However, the engineering challenges are significant. If these aren't handled well, a 3rd-party pack could be disappointing.
install vidmate
Posts: 1
Joined: Sun Aug 28, 2022 10:41 pm

Re: i3 HV Battery Upgrade

Does anyone know. This upgrade still averrable? I live in San Jose, CA, USA. Where I can install it?
Posts: 18
Joined: Tue Nov 15, 2016 12:44 pm

Re: i3 HV Battery Upgrade

$21.3K for 260 miles ... plus the cost of the i3 much is a Tesla Model 3 again? I think these upgrades would make sense if they were about 30% less costly. If an older i3 costs about $10k and it could have 260 miles of range for about $32k total, this makes good sense in my opinion.

Generally newer is better, so I would be surprised to see anyone buying an older car to upgrade its batteries for the same or greater expense...when they could just pick up a newer car and get the same range and the peace of mind knowing someone did not partly disassemble their car and reassemble it which on its own creates a risk for mechanical issues.

Also would an insurance company insure these packs...etc?
Posts: 2
Joined: Thu Dec 15, 2022 3:46 am

Re: i3 HV Battery Upgrade

Here is my statement then I will follow up with my question. I am currently having a warranties battery swap done on my 2015 i3 and I anted to upgrade the battery pack for greater miles so this product interest me greatly. Please send details as far has how do I sign up!
Here is my question. The replacement required a reprogramming of the car and that reprogramming I am told removed the regeneration function from the car. So instead of one pedal driving the car will now coast. Does your programming for the upgrade solve this problem? What functions are added ir removed due to your reprogramming of the car?
Posts: 2
Joined: Thu Dec 15, 2022 3:46 am

Re: i3 HV Battery Upgrade

Can you contact me about this, I would be interested in doing this to my car. ;)
AgentiMi wrote: Tue Feb 16, 2021 1:53 pm (This is a repost from the i3 Reddit page.)

I work for a stationary energy storage company and I need an excuse to develop i3 batteries.

I wanna know just how many of you would actually buy an upgraded battery.... they are pricy... almost as much as 2 used i3s.

Here's what you will get IF we make this product:

-10-year capacity warranty.

-Increased range.

-Increased power output of the pack for modified applications.

-Faster DC charging, from 40kW to 250kW peak.

-Battery condition on climatize.

-We'll offer installation and financing.

The modules are already developed for our large stationary storage systems (300kWh+) an example application is DCFC stations. We are playing with the idea to put these packs in classic cars and it hit me. Why not the i3? or any EV.

I've made a list of possible configurations below, please vote if you would actually buy one if it was offered.

Side note. You will also need different springs and dampers in some applications, good luck.


Cost values are for the battery pack only.

Range values are estimates in COMFORT mode driving.

kWh values indicate total usable energy and do NOT include battery buffer.

We are not asking for money. This is just to show you how much a battery pack will cost.

**** may require a different battery tray, adding to the cost.


Here are the possible configurations listed below.

~80 miles (129km) 19kWh $6K (50kW DCFC)

~120 miles (193km) 30kWh $9.8K (70kW DCFC)

~160 miles (257km) 40kWh $13K (100kW DCFC)

~260 miles (257km) 69kWh $21.3K (150kW DCFC)

****~320 miles (515km) 90kWh $24.5K (250kW DCFC)


I'm happy to answer questions!

We're also hiring for more engineering positions soon. Maryland and remote. I'll post about it.
Posts: 1
Joined: Tue Jan 17, 2023 9:11 am

Re: i3 HV Battery Upgrade

I'd do the 30 or 40

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