Hi,
.
For our project, we decided the below requirements:
Battery Type: Lithium Ion
Battery Dimensions: 18650 (18mm Diameter, 65mm Length)
Topology - Parallel (1s2p, 1s3p or higher)
Requirements
- Since both Li-Ion batteries are connected parallel, both battery should be able to charge evenly, and use batteries evenly.
- Protection circuit for Short, Overcurrent, Overvoltage, Overtemperature etc.
If one battery damaged, no change to circuit, remaining batteries operate as usual.
- Should allow charge state to be measured accurately.
- Maximize the number of cycles. Accurately charge to required max voltage.
Details
- 4.2V Max Output for Charger.
- Allows either USB or DC voltage input to charge. (suggest switch mode ??)
- Allows charging while operating.
- Pre-charge, CC, CV, Terminate. Charge evenly all batteries at 1C or less at same time.
- Battery Gauging
- Should account for load/no load, temperature variation.
(TI has 'Impedance Track' feature & Voltage Profile Database)
For bq40z50-R1 fuel gauge, it is supports up to four series cells.
We also looking at the BQ27500-v130....
Can it be used to monitor the battery system as proposed?
But we plan to charge the battery in parallel as mentioned above.
Is there any suitable battery charger or fuel gauge that fulfill the requirements?
Please refer attachment:
