How would be your Ideal BMS? - Page 1
Forum section: electronics / projects

author: joaoantoniocardoso
author_rank: Newbie
timestamp: June 11, 2018, 01:54:33 am
content: Hi!Battery Management Systems (BMS) have been used for a while and I’m sure that there are quite a few good options in the market,but do they meet our needs?Trying to understand the real needs from the community, i’m here today to investigate about what clearly isn’t a simple question:How would be yourIdeal BMS?I’m an electronic engineer student and to first start it, I am doing a easy and fast survey about what features would have anIdeal BMS.To bring some benefit to this awesome community, the results will be openly posted here (in about 3 weeks), while all personal data will be deleted just before.LINK TO SURVEY:https://goo.gl/forms/WyZxMPgQQqLP9Gy83Cheers!!

author: Dubbie
author_rank: Unknown
timestamp: June 11, 2018, 02:34:55 am
content: I wish there was a simple IC that took 5V in and BALANCE CHARGED a 2S battery as well as provided passthrough power.I've only ever found one or two ICs that do balance charging and they are hideously complicated.

author: Ornuimar
author_rank: Newbie
timestamp: June 11, 2018, 10:45:38 am
content: I'm also deciding what to do.casino online

author: Siwastaja
author_rank: Super Contributor
timestamp: June 11, 2018, 11:55:25 am
content: Reliable, safe, and sanely designed single-IC solution which wouldn't either underdeliver or overdeliver.I.e., hard OV and UV levels with sane default configurations for normal cases, meaning LV cutoff between MIN 2.5V MAX 3.0V, and HVC between MIN 4.20V MAX 4.30V over the complete intended operating range on every device guaranteed.Maybe a basic balancing algorithm that can't get left stuck on by accident, and wouldn't require microcontroller interaction. But I guess this is too much to ask for in the current situation where they can't even get the combinatorial limits right yet. Safe and effective balancing almost always requires some state and state is a can of worms.With application notes not written on crack by student summer workers, because let's face it, many designers do copy those designs, and if the designs pose an imminent fire danger, it's better not to publish them at all.To me, it seems that the BMS ICs are specified by software guys, designed by IC design students, without consulting the battery industry or actual battery system designers, or seasoned IC designers. They seem to be "fun-to-play" products for the "sparkfun generation", made by "let's write million lines of Verilog" generation, where the more you spend time on doing random things over I2C bus and printing it to the UART, the better it is.Manufacturers don't seem to have any issue with offering their chips in 30 different configuration, and Digikey doesn't seem to have any issue actually stocking more than half of them! In reality, there are about two or three li-ion chemistries in use, and if the IC manufacturers consulted li-ion experts before designing li-ion products, they might come up with the correct cutoffs and algorithms with smaller range of products, possibly only one.Instead, the market if still flooded with overcomplicated products that mostly do wrong things, and simpler products that left some vital part out and hence are of no use. We have expected this would get better for years, but it's clearly not happening.Not using cell level management or balancing at all is still often a best option, and I'm not surprised it's still widely used in the industry for li-ion packs, especially 2s.

author: timpattinson
author_rank: Contributor
timestamp: June 13, 2018, 07:58:59 am
content: This really depends on what kind of battery you are managing. As an extreme example, a drone,laptop,IoT thing, power tool etc vs. a full EV (hundreds or thousands of cells).Which variety of BMS are you thinking of?