2 hardware solutions, one for cell quality check (for mission-critical battery packs), one for R&D (cell characterization)
Safion is now associated with Digatron, battery testing equipment manufacturer. This will probably replace their Digatron EIS Meter, which can be connected to their Life Cycle Testers
“Research and development” - Intended for lab and battery research use
~30k€
Inspectrum.C
MUX8
8-channel multiplexer
Questions to Safion
Workings
What are the customizable quality criteria?
App dependent. Refurbish: grades. Average aging. Residual life. Impedance spectra provides a much better indicator of SOH than capacity.
1kHz impedance doesn’t give good health assessment. Not sensitive to aging
“Precise prediction of battery performance and lifetime” ⇒ more info?
Does it give indications on cell capacity? At least relative inside a group of cells?
Not capacity
Possible to have multiple output criteria for multiple output bins?
Yes
does the cell voltage affects the measurements (in case all cells are not balanced) ?
ExaMight
How much time / manually tested cell on ExaMight solution?
Manual ⇒ 6s per cell
Automation line ⇒ 4 cells per second
Inspectrum
What kind of wiring do you provide, cables / connectors / cell holders?
“derive an electrical and thermal model of your battery in a simple and fast way” ⇒ more info?
What kind of tests are carried out generally?
Parameters vs temperature? Aging?
DC current +/- 1A only?
More than 8-ch multiplexer for more cell tests?
Can we integrate Inspectrum in our own automated system? Seems like yes
What data is available on the CAN interface?
Workflow
Tracking each cell vs making bins with similar characteristics?
MB Elec information
Classic EIS machines take a few minutes per test and cost upwards 100k€
Safion: reduced spectrum to the one useful for batteries and 32 simultaneous frequencies, so faster (~1s). Also a cheaper solution
💡
Demo machines available in a few weeks-months
Integration
Could be used instead of
Call with Alex from Safion
Other service: model the cell. take aged cells, age new cells and correlate, they give life time estimations.
ExaMight old cells, grade them A B C D E. Then capacity test. Capacity in a grade in the same ballpark. Company provides this process also. Not on website
Partially discharge
Inspectrum in parallel of the cycler. Parameters along aging, slew rates, temperatures
They provide integration kits with ExaMight. Automation. German and Indian companies that already automated for large volume
Advise barcode on every cell for traceability
Pictures of automated machines
Demo unit next month to MB ? Shortages
Remote demo. Automatic system show in 3d models. Sign NDA
Call tomorrow with MB, then we arrange a remote meeting
Send 10-20 cells, they test and provide the data, we cycle to verify
Digatron partnered for credibility
18 people, growing from business
Metting with Rodolphe Herrerro
More than 1 muxer, up to 32 channels. Measure chains, up to 60V
Temperature compensation during test?
Test 1 cell at 100% and 1 cell at 0%, same model?
Assess self-discharge?
Measure a panel of cells of the same model with different capacities. Send to Safion and get the results. Can we infer the capacity from the test results? Can we assure a minimum capacity?
Remote Demo 08/03/22
Florian Goubert, Benoit Hervieu, Alexander Gitis (co-founder & CEO)
Can provide fully automated system with wanted throughput
Even for new cells, quality deviates. Assessment for 1st life. OEM car companies test each cell more and more
Good reasons not to trust the datasheet. NDA related equipment
Prepare the cells for SOC conditioning. 35%
Module from a better grade > module from lesser. Better battery life
If battery is 0% or 100% at impedance measurement, not a good indication. 0-10% or 90-100%, difficult to produce a good measurement
Need at least 30% SOC (20-80%) for best results. Correction model (addition development) for 30, 40, 80% to not have to discharge
On the cyclers, load to 30% SOC. New cells come at 20-40% so 10% charge or discharge
Use for pre-assessment : this one is bad for sure (pass-fail)
SOC adjustment (not full capacity)
Grading with Safion
They can build an automated machine
Customer: usually 3-4 grades. Could do more, but accuracy would overlap. Weakest
Different cell models question: challenging problem (Alex)
Not in parallel, current sharing
Cells which had faster discharge was hotter, most of the power comes from it. Ages more
Get an equivalent circuit model for each cell with Safion
As a service: life time prediction of different cell types. Impedance test and cycled by Safion. Correlate the impedance data with aging. Accuracy of 10%. e.g. 600 cycles
Send interesting cells in the 1000s tested
Worse impedance cells get hotter so age faster
You can avoid cycling : Our system provides about the same accuracy on capacity (estimation). Good correlation with capacity
Not full capacity test = lose a bit of accuracy on capacity but faster
Export function
Can use the equivalent model to match the cells better
Some 2nd life cell supplier deliver a lot of bad cells. Can analyze on the system
We can start with the manual machine (MB Elec end of month) to get the first 100s cells to get a good feeling
Advises this process: pass fail, then SOC adj, then good assessment
Then proof of concept for the investors
If satisfied with the process, automate
Mercedes AMG, 30000 cell per day. 4 channels
Partner for automation, they provide integration kit. Or German partners. Or do it ourselves
Will send some slide, NDA
Every single test has a code and is tracked
Most cells have one
6s per cell
From different batches and ages
1 kHz. All are close so this is why 1kHz measurement oes not work
Wear gloves
Absolute is based on 1000s previously measured cells if you have
Color :
Bins:
Typically, another menu with pass-fail or different grades, can be customized
3000-4000 cells tested per day (600 cells per hour)
Use the manual system for the first clients / batches
Kit is ExaMight Control unit (mounting holes) + contacting heads and temperature sensors
Build machine that carries the contact heads
CIT (travailleurs handicapé) or intérim
Cell model example. RRC model with the OCV parameter
More information on kit (NDA)
More information on automation with partner. Cost and lead time
How much does cycle life estimation service cost?
If we cycle them they need the cycle number?
If they cycle they we provide
At least 12 weeks lead time from now for the system including MB Elec
Integrated system cost depends on throughput. Price indication. Follow-up meeting
Indication for the integration kit
For fully automated system, more complex, have to involve automation partner
⇒ Buy battery cyclers
⇒ Buy IR testing machine?? Or manual at the beginning? Integration with this machine?
An automated machine would work 24h/24 + week-ends ⇒ 3x the thoughput. Night keeper, fire extinguisher...
