Better BMS. (Photo: Blue Mountain State) James Post Managing Director. Battery Condition Test International Ltd. Hong Kong

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1 Better BMS (Photo: Blue Mountain State) James Post Managing Director Battery Condition Test International Ltd. Hong Kong

2 Introduction James Post Executive in high tech electronics in the Netherlands since 1975 Power electronics, [embedded] software & data communication Strong in conceptual design

3 Introduction James Post Co-op with partner Alexander Kool (Engineering Spirit) since '75 Translates problems to solutions The BA 500 is a perfect example

4 Introduction Company The BA500 battery tester was developed by Engineering Spirit BV, the long time Dutch partner Battery Condition Test Intl. Ltd. handles all marketing & support

5 Introduction Company Before starting R&D, an extensive market study was performed Objective: ensuring the product would meet customer's demand

6 BA500 Profiles Concept All data on how to test particular batteries is stored in profiles Operation by the user is therefore simple: connect battery and charger, select profile (can be by bar code reading), press START

7 BA500 Profiles Concept The warranty profile data is to be provided by the battery vendor Usability profile data is defined by OEM and simulates the real world This ensures correct data!

8 BA500 applications Nominal voltages V; 500W (other ranges can be defined within a factor 2 dynamic range) 750W & 1500 models Summer '13 Easy up-scaling to higher power

9 BA500 applications First major use is e-bikes/scooters Used in both QA and for customer service purposes by dealers BA500 was certified for warranty handling by e-bike dealers

10 BA500 BMS Support Ability to read and interpret BMS data as per customer instruction Interpretations come in the report Can identify bad cells individually

11 BA500 BMS Support Reports too high temperatures as specific/accurate as sensors allow Reads moist in and deformation of battery pack when supported

12 But... There is a problem! Most BMS can not accurately monitor batteries...

13 This is why we started Better BMS

14 Objectives * Substantial improvement of QA results * Monitoring battery pack during usage to timely see safety issues

15 Basics Measures each cell individually Intelligently stores cell & sensor histories to identify later issues Basics will become public domain

16 Basics Multiple sensors for temperature, moist and deformation in pack Supports enough sensors to allow accurate determination of issues This is our gift to the industry!

17 in QA Bad cells are easily identified and replaced before sealing the pack After sealing the pack a quick test for leakage & deformation further reduces (future) warranty claims

18 during use In the real world, battery packs can be abused (inadvertently) During operation Better BMS will register deformation and leakage as well as under-performing cells

19 Cooperation with CALCE Center for Advanced Life Cycle Engineering (University of Maryland) A major laboratory, specialized in testing lithium batteries & BMS 110+ highly specialized staff

20 Milestones August 2013: Base specs to be made availability to BMS partners October 2013: Comparative tests under controlled conditions that promote thermal runaways; Better BMS timely switches off

21 Milestones November 2013: Presentation of test results at Battery Safety Conference (San Diego 13/14-11) Spring 2014: expected release of first Better BMS

22 Partnership Potential partner(s) must have direct control over BMS Software Partners make battery samples available for destructive testing

23 Partnership Partners are provided with safety algorithms and sample code for implementation Partners will be the first to hit the market; benefit from positive PR!

24 Thank you for your attention!

25 If time allows I will present a bonus: How to prevent recalls

26 How to prevent recalls Recalls are expensive and hurt the image of battery vendor and OEM Not counting bad design, causes are flaws in QA from cell to pack

27 How to prevent recalls The objective is to recognize issues before pack distribution Solution: expose batch samples to an accelerated life cycle test

28 Sample test procedure Take a small quantity out of every batch (i.e. 6 samples for 3,000) Expose the battery to 120 full charge/discharge cycles in a climate chamber (takes 1 month)

29 Sample test procedure Vary temperature, moist in accordance to field conditions Expose the battery to vibrations monitor BMS during test!

30 Sample test impact Harmful chemical cell impurities that were not recognizable will likely cause issues during the test Mechanical failures (i.e. leaking) will likely show up during the test)

31 Sample test cost This test cost US$ 0.11 (based on 2/1000 samples; tested in China) Test cost based on BA500 (500W) Less than 0.1 % of battery cost! Much cheaper than insurance...

32 Not science fiction: Common Sense... Q:

33 E-bike dealers afford the BA500 (US$ 800); also lowest cost automatic life-cycle tester