Adoepner
Posts: 47
Joined: Mon Jul 01, 2019 10:08 am

Re: Cost to replace an i-miev battery?

Sun Mar 29, 2020 11:03 am

Hi Enginerd,

Who is your supplier for the LG 21700s?

Andrew

datom
Posts: 20
Joined: Wed Apr 11, 2018 8:01 am

Re: Cost to replace an i-miev battery?

Mon Mar 30, 2020 12:24 am

Adoepner wrote:Hi Enginerd,

Who is your supplier for the LG 21700s?

Andrew


Hi,

NKON has them for €4,95. https://www.nkon.nl/de/lg-inr21700-m50-5000mah-7-3a.html

Adoepner
Posts: 47
Joined: Mon Jul 01, 2019 10:08 am

Re: Cost to replace an i-miev battery?

Tue Mar 31, 2020 11:03 am

Do the LG 21700 cells have a high enough current rating? They are rated for 7.3A.

An LEV50N is capable of 300A continuous (https://pushevs.com/2015/11/04/gs-yuasa ... vs-lev50n/). You would need 41+ of those LG cells in parallel to be able to deliver a rated 300A. I don't think there is enough room to replace each LEV50 with 41 21700s. A practical maximum I've seen is in the neighbourhood of 20x21700 per LEV50 using this circle packing calculator (https://www.engineeringtoolbox.com/circ ... _1905.html).

Unless we know with certainty what the maximum current the car will draw under any circumstance, I'd only be comfortable replacing like-for-like as far as battery specs are concerned. Lower amperage cells have a higher internal resistance and heat up more under load (and charge).

Andrew

datom
Posts: 20
Joined: Wed Apr 11, 2018 8:01 am

Re: Cost to replace an i-miev battery?

Mon Apr 20, 2020 11:43 pm

Enginerd wrote:20 x 21700 LG M-50 cells ordered and on their way for initial testing.

....

Enginerd, Did you try the 21700 cells already?


nuggetgalore
Posts: 14
Joined: Sun Apr 12, 2020 12:46 am

Re: Cost to replace an i-miev battery?

Sat Sep 05, 2020 5:01 pm

jray3 wrote:Good luck to you, Enginerd! The similar Aussie effort has stalled, and now that I have a 75 mile one-way commute, MR BEAN in on greatly reduced duty, only doing about 250 miles per week of wifely driving, while I do that much per day on a 27 kWH Kia SOUL and my company car, a z2012 LEAF that we have upgraded to 40 kWH with an 2018 battery.

Hi all,
am I correct that "The similar Aussie effort" refers to the 60 Ah cell replacement started in Perth WA?

https://forums.aeva.asn.au/viewtopic.php?f=49&t=5515
or a bit further down:
https://forums.aeva.asn.au/viewtopic.ph ... &start=275
Anyway, I am now continuing this project.
There are still many questions to be answered, many of those issues only become known as the project advances.
Because of the different shape of the LiYuan cell compared to the LEV50,
the project was started with the cells standing up rather than laying on their sides. Yes that works as far as physically fitting them into the base
The BMS boards will be mounted onto a specially made board so each cell can be connected to the correct spot on the BMS board.
Thinking about that a bit further,I am concerned now that the module may overheat. Two main reasons for that concern are that
a) on the original modules the BMS board including the temperature measuring devices are hidden at the sides of the modules away from the cooling air that hits the cell bodies.
b) worse is that with the BMS boards sitting on top of the cells, the cooling air is going to cool the temperature sensors rather than the cell bodies, giving a false reading of what on the original set up is more like an ambient module or pack temperature.
Any comments would be greatly appreciated.

jray3
Posts: 1704
Joined: Tue Dec 06, 2011 1:05 am
Location: Tacoma area, WA
Contact: Website

Re: Cost to replace an i-miev battery?

Thu Sep 10, 2020 12:50 pm

Enginerd, glad to see that you're moving forward. I read that the project in Perth is having trouble in that the pack works and the car drives beautifully, but the additional capacity is not recognized because the car won't go past a 49 Ah discharge, regardless of cell voltages. That's interesting, and very different from an early LEAF. I wish all of you the best of luck.
2012 i-SE "MR BEAN" 110,300 miles
2016 KIA SOUL EV, 90 kW, 27 kWh, 34k miles
2000 Mazda Miata EV, 78 kW, 17 kWh
1983 Grumman Kurbwatt EV,170 kW, 32 kWh
1983 Mazda RX-7 EV 43 kW 10 kWh
1971 "Karmann Eclectric" EV 240 kW 19 kWh

nuggetgalore
Posts: 14
Joined: Sun Apr 12, 2020 12:46 am

Re: Cost to replace an i-miev battery?

Mon Sep 14, 2020 3:16 am

jray3 wrote:Enginerd, glad to see that you're moving forward. I read that the project in Perth is having trouble in that the pack works and the car drives beautifully, but the additional capacity is not recognized because the car won't go past a 49 Ah discharge, regardless of cell voltages. That's interesting, and very different from an early LEAF. I wish all of you the best of luck.

The project you are referring to is using 93 Ah cells and is in Brisbane.

The "Perth" project (with 60 Ah cells) is now in Melbourne and waiting for the covid -19 restrictions to end for further progress.

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