LiFePO4 battery pack - Page 1
Forum section: electronics / beginners

author: br4n_d0n
author_rank: Contributor
timestamp: May 30, 2023, 02:41:04 pm
content: I would like to make a battery pack to charge my cellphone using LiFePO4 batteries, but I'm not sure where to start as I'm new to this.Can someone point to a simple tutorial for a beginner?

author: BILLPOD
author_rank: Frequent Contributor
timestamp: May 30, 2023, 07:08:29 pm
content: There are a LOT of 'Power Banks' for sale on the interweb. Here's just one example:https://www.amazon.com/30000mAh-Portable-Charger-External-Compatible/dp/B09TPFGXMS/ref=asc_df_B09TPFGXMS/?tag=hyprod-20&linkCode=df0&hvadid=658456414704&hvpos=&hvnetw=g&hvrand=9917301598418975934&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9005066&hvtargid=pla-2061589462522&psc=1&gclid=CjwKCAjwvdajBhBEEiwAeMh1U_p7YPyNbAL63WKZ3JPZUF4gK2TTGUuqHrszTzArToNUXUPRKW4LABoCkccQAvD_BwE

author: LooseJunkHater
author_rank: Frequent Contributor
timestamp: May 30, 2023, 07:14:16 pm
content: Any reason why you want to make it from LiFePO4? For this application, LiFePO4 cells are kinda a poor choice.

author: br4n_d0n
author_rank: Contributor
timestamp: May 30, 2023, 11:36:23 pm
content: My reasoning is that LiFePO4 last longer and are less of a fire hazard as far as I know.

author: LooseJunkHater
author_rank: Frequent Contributor
timestamp: May 31, 2023, 12:07:01 am
content: Quote from: br4n_d0n on May 30, 2023, 11:36:23 pmFor most people the power bank cells out-live the actual power bank so I can't imagine that being a significant factor for you. Further, while LiFePO4 does have a significantly lower fire risk, most lithium battery technologies already pose such an incredibly small fire risk (think 0.01% and less). The amount of actual *energy* in a power bank is quite insignificant and power density is of a much bigger factor, hence why most OEM's don't use LiFePO4 cells.If you're still dead-set on going with LiFePO4, you will need to get an understand of what a BMS is (and ensure you know the difference between a standard lithium battery BMS and a LiFePO4 BMS), what boost/buck technology is, a batteries "C" rating and constant-current delivery capability, as well as the input voltages supported by the actual USB power delivery circuitry. This information isn't at all "simple" and requires some knowledge on electrical engineering. You may be better off utilizing a "kit" of some kind.

author: Jwillis
author_rank: Super Contributor
timestamp: May 31, 2023, 02:05:47 am
content: LiFePo4 emergency battery packs are available from Talent Cellhttps://talentcell.com/lifepo4-battery/12v-6ah/lf4100.htmlAlso available on Amazon.

author: MrAl
author_rank: Super Contributor
timestamp: May 31, 2023, 02:08:54 pm
content: Quote from: br4n_d0n on May 30, 2023, 02:41:04 pmHi,This could be fun but you better get it right as some cell phones cannot take much more than 5 volts in the USB charging port.I happen to like LiFePO4 batteries myself due to their safer nature. You can get 12-volt units and then you can buck it down to 5v.I think they also make 6v units but that would probably be a waste of time. For 12v feeding a buck putting out 5v, you can get about twice the ampere hour capacity going into the charging port. That's because if you charge at 1 amp the 12v battery will only have to put out roughly 1/2 amp.Much simpler and less hassle to buy a ready-made battery.