AEVA Forums

I've finally finished reassembling the battery modules. The cells are now 4 in parallel, 43 in series. Fully charged, this would be 179 V. But my charger doesn't charge that high, it cuts out at 172.2 V. This will therefore charge the cells to a maximum of 4.00 V per cell, or about 90% state of char...

Mate, we at AEVA never discourage folks from embarking on a conversion project. Speak for yourself, I'm sure I've discouraged plenty of folks by sending them to my build thread! Here it is, the thread for my Brumby: https://forums.aeva.asn.au/viewtopic.php?f=33&t=2418 As Chris said, you'd need a mo...

Ok, I reckon this is pretty interesting, so I made a news post on the main AEVA website. You can view it here: https://aeva.asn.au/news/fast-charging-your-bmw-i3/ Hopefully this advertises the idea a bit further. As a branch secretary, I send an email to our membership each month with these sorts of...

I know someone who might be interested, but I'd need an indicative price.

The 1st gen EVs (leaf, imiev, i3, etc) came to australia with type 1 ports, so the first roll out of charge stations were type 1. There are still a significant number of type 1 charge stations in Australia, though no new ones are being installed. But are there any Type 1 sockets installed? The only...

I was just thinking about the cars cabin heater, since the motor is liquid cooled, i wonder if it would be possible to connect the cabin heater to the motors cooling system. Not sure how cold it gets where you are, but I can give you some real-world experience. On a cold day, my motor doesn't get a...

I have a 720 CCA Acid battery already in the car, and that can power my car fridge/freezer all night and still leave enough power to start the ICE in the morning, have been looking at Automotive deep cycle batteries as well, to replace the factory 12V system battery. found these https://www.century...

As always with EV conversions the biggest expense will be the Traction motor battery packs, On average I do about 150 to 160 Klm's a day for work, so i am going to require enough batteries to give me at least a 300 to 350 Klm's range, As you say, the biggest expense. Off the top of my head, 350 km ...

Rob You mentioned: "Most EVs have a separate 12V battery for "house" electrics and charge that with DC-DC charger powered by the traction pack." Are these what you where referring to ? https://www.evworks.com.au/start-saver-battery No, Rob's talking about something like this: https://www.evworks.co...

jonescg wrote: ↑Tue, 09 Jun 2020, 21:49 Oh, the really good numbers are downhill. The higher numbers are uphill. There's about a 250 m elevation difference between home and work.

I was sure you were going to say that the good numbers are Katherine, and the higher numbers are Chris.

The Voltage is around 72 V. It's not so much getting the energy, back, it's maintaining constant rpm during downhill. In low gear you could easily explode the motor. This is a good thought! I'm also looking at converting a tractor, and I had assumed that DC was the only way to go. Here was my reaso...

Water will absolutely kill a cell in short order. The pouches are made of a bi-layer of polythene and aluminium, but the polythene is peppered with microscopic holes. These allow the aluminium behind it to corrode, eventually penetrating the cells and spoiling them. Any idea how much water is bad f...

The Tasmanian Government has taken the approach of subsidising the infrastructure. As a result, we are getting about 15 new DC fast chargers this year, up from 2 total in the state before that. This is in a state of 500 k people. 17 DC fast chargers mean that the entire state is covered. If you're o...

That Brillo scourer material is quite abrasive (if that's what it is). No, not scourer. This stuff is more dense, thinner and softer. I've spent the past couple of days dismantling and re-assembling battery modules. Re-polishing all the connections and doing up the roughly 300 fiddly little bolts a...

Here's what I'm doing now, following the advice gained here (mostly from Chris). IMG_0474.JPG Steel springs now have Kaptan tape on the side that touches the cell tabs (which are either aluminium or plated copper). IMG_0468.JPG More Kaptan tape, covering the corners of the cells to stop them making ...

Back to work again for the weekend and I found out some more info. I checked the current flowing from between random points on the ends of the cells. In most cases it was negligible - so little that just measuring the voltage with the multimeter made that voltage drop over a few seconds. I tried one...

Ok, here we go. IMG_0454.JPG IMG_0453.JPG IMG_0455.JPG IMG_0456.JPG I reckon this quite possibly my problem! I tested a few cells, and some display this feature more easily than others. On this one, which is one of the ones that got hot, it was very easy to find a place that would give me a voltage....

Can you tell me how many cells are leaking? So far there are 8 out of the 65 that I've checked that have some damage. 2 are leaking outside of the pouch and have burn marks. 4 have burn marks but no external leakage 2 have signs of leaking within the pouch but no burn marks. The aluminium next to t...

I'd coat it in Kapton tape, or at least some kind of contact adhesive, and make sure that you put a layer of something with a bit of give, like thin EPA or double-sided tape. Ideally you would glue the cells in position, but if you want the option of pulling them apart again, these would be the lea...

Yes I certainly wouldn't be packaging pouch cells against bare metal, especially not where it might rub. The pouch itself is a composite of aluminium and polymer, but the polymer is vanishingly thin - and effectively peppered with microscopic pinholes. Any moisture or humidity that works its way in...

I run the cells for at least 10 cycles at 1C from 4.2v to 3.0v and at least 4 cycles at 2C. This was when I was checking the capacity. After that I have used for energy storage for a battery tester but at very low C rates. The battery tester cycles NiMH prius cells. It is mainly used for recovering...

Did you do a check for stray voltages between (+) and chassis? If you do spot something, it's worth checking the current with a decent ammeter (don't forget to swap the cables back once you're done!). Should be well under 30 mA. I've just thought of something. The cells butt up against an aluminium...

The road is a brutal environment for cells. They really need to be well protected, snug, and unable to rub of fret against anything. Or reside in tension - eventually something gives way, and the opportunities for cascading problems start to pile up. Likely there was a leakage current to chassis? D...

I have had a pack of these cells assembled for over a year and didn't have any leak and they still seem to be working fine. I can not explain why you are having such a high failure rate. Is there any chance you could have pulled the tabs while tightening the bolts and damaged the inside? Assembled,...

So what happened? Why have these cells gone bad? With this fastening system the top and bottom cells in each pile of 10 have quite an angle on the tabs. The first failure I saw was one of these. But since then I've found others that were not the furthest ones, but ones in the middle where the tabs a...