This is quite the multipart and deep question. You seem to understand the basics but just in case, I’ll recommend this website as a good overview, albeit dated in terms of current ICs and BMS competitors.
http://liionbms.com/php/index.php
Chips
This is dependent on application. For small packs like the one you’ve drawn, there are a wide variety of chips available. For larger packs, Linear (LTC6803) and Maxim (MAX11081) are the two main competing suppliers of BMS solutions. They provide the most integrated solutions for multi-cell management. The main differences from smaller packs are the higher series voltages, daisy chain communication and noise immune signaling.
Techniques
In either case, voltage monitoring, temperature monitoring and active balancing tend to be the primary needs of a BMS. Other features such as redistribution tend to be less critical and often do not warrant the added cost and hardware.
Solutions
Unfortunately, even though nearly all BMS designs have the same goals, rarely is there an all in one solution. Solutions are based on number of cells, voltages (chemistry), tolerance for loss, communication method etc. These variables are not all standardized between one project and another. Furthermore, technologies keep changing. Linear is considering replacing CAN-BUS with shielded Ethernet. ADC accuracy is increasing. Sample rates are increasing.
The tried and true method is just simple active balancing. That is extra voltage on a cell is bled off resistively. Other than that, the rest of the system is a simple matter of reading all the cell voltages efficiently.
The Future
Eventually, we will see a more robust landscape with better standardization. Companies like Elithion or Nuvation are designing BMS solutions that are nearly drop in solutions. Chip designers are getting a better understanding of customers needs and have already sought to distinguish between the different types of li-ion needs based on different industries. This will mean that we’ll start only paying for features we need. Even battery cell manufacturers are standardizing cell types. For now though, any battery design remains quite customized.
Both types of construction have similar characteristics in terms of degradation, charging behavior, and susceptibility to deep discharge problems, but:
Li-Polymer have a slightly higher energy density because of the way in which the separator (salt bridge) is made. This comes at a 10-30% increase in cost, however.
It's possible to make flexible batteries with Li-Polymer, and to make them thinner than Li-Ion.
Source: http://www.allaboutsymbian.com...
Best Answer
Li-ion batteries usually follows the naming convention according to size, so for example an 18650 battery is 18 mm in diameter and 65 mm in length. 0 denotes cylindrical form.
In the past, a tailing 5 wound indicate a prismatic cell but yours doesn't.
Anyhow, my best educated guess is that 35 denotes the length, 08 the width and 3 the thickness and all measurements in millimeters.