Martin's DokuWiki

User Tools

Site Tools

You are here: start » life_hacks » battery_tips
Trace: • fluids • playstation • rlink2 • bakingsoda • lights-leds
life_hacks:battery_tips

Differences

This shows you the differences between two versions of the page.

Link to this comparison view

Both sides previous revisionPrevious revision
Next revision		Previous revision
life_hacks:battery_tips [2025/10/14 03:30] – [No batteries: the magic and curse] adminlife_hacks:battery_tips [2025/11/20 23:03] (current) – [IEC LiPo size convention] admin
Line 2: Line 2:
  
 TL;DR (simplified): Lithium batteries are dirty. Do not store empty or fully charged (recharge every ~6 months to ~50%). Dispose correctly, always salvage the BMS. Alkaline batteries will leak corrosive acid: do not leave them in stored devices. \\ TL;DR (simplified): Lithium batteries are dirty. Do not store empty or fully charged (recharge every ~6 months to ~50%). Dispose correctly, always salvage the BMS. Alkaline batteries will leak corrosive acid: do not leave them in stored devices. \\
 +
 ===== No batteries: the magic and curse ===== ===== No batteries: the magic and curse =====
  
Line 11: Line 12:
  
 Also interesting: There is a page called [[https://batteryuniversity.com/articles|batteryuniversity.com]]. \\ Also interesting: There is a page called [[https://batteryuniversity.com/articles|batteryuniversity.com]]. \\
 +
 +===== Tests & Reviews ======
 +
 +[[https://lygte-info.dk/info/indexBatteriesAndChargers%20UK.html|lygte-info.dk: Batteries and chager tests]] \\
 +[[https://lygte-info.dk/info/indexUSB%20UK.html|lygte-info.dk: USB wall charger tests]] \\
 ===== Disposal ===== ===== Disposal =====
  
Line 41: Line 47:
 __How lithium works__: Lithium ions shuttle between the cathode and graphite anode during charge and discharge, storing and releasing energy. \\ __How lithium works__: Lithium ions shuttle between the cathode and graphite anode during charge and discharge, storing and releasing energy. \\
  
-**Nominal Voltage is ~3.7 V per cell, 4.2 V per cell when fully charged.** \\+**Voltage is 4.2 V per cell when fully charged. \\ 
 +Nominal Voltage per cell is 3.6V for Li-ion (cylindrical / LiCoO₂) and nominal 3.7V for Li-Po (pouch cells). ** \\
  
 +==== IEC LiPo size convention ====
 +
 +According to **IEC** LiPo sizing convention e.g. a 404343 battery is 4.0x43x43 (Height x Width x Length in mm). \\
 ==== Charging ==== ==== Charging ====
  
Line 101: Line 111:
 Empty storing (aka forgetting the battery): Do not store lithium batteries empty. They die if voltage drops below 3.0V. Safe minimum under normal use is 3.3 V. Everything below 2.5V per cell is a danger zone (don’t attempt revival)! Do not attempt to trickle charge them for revival. \\ Empty storing (aka forgetting the battery): Do not store lithium batteries empty. They die if voltage drops below 3.0V. Safe minimum under normal use is 3.3 V. Everything below 2.5V per cell is a danger zone (don’t attempt revival)! Do not attempt to trickle charge them for revival. \\
 When voltage drops too low, copper from the anode can dissolve into the electrolyte. On recharge, this copper can plate back onto the cathode as tiny dendrites, which may pierce the separator and cause internal shorts — leading to swelling, overheating, or fire. Recycle deep discharged battery. \\ When voltage drops too low, copper from the anode can dissolve into the electrolyte. On recharge, this copper can plate back onto the cathode as tiny dendrites, which may pierce the separator and cause internal shorts — leading to swelling, overheating, or fire. Recycle deep discharged battery. \\
 +
 ==== BMS salvage and re-cell ==== ==== BMS salvage and re-cell ====
  
Line 113: Line 124:
    * **DRM**: authenticate as original battery (some systems refuse to work with 3rd party batteries) - this is why you need to keep the BMS board!     * **DRM**: authenticate as original battery (some systems refuse to work with 3rd party batteries) - this is why you need to keep the BMS board! 
  
-Due to the protection feature it can be that you measure 0V on an empty battery - the cell itself can still have a charge. This does not necessarily mean that the cell is dead, it still can have ~3V and be safely rechargeable. When disposing of the battery, cut off the BMS and discharge the cell itself. \\+Due to the protection feature it can be that you measure 0V on an empty battery - the cell itself can still have a charge. This does not necessarily mean that the cell is dead, it still can have ~3V and be safely rechargeable. Before disposing of the battery, measure cell voltage. Cut off the BMS (keep it!) and discharge the cell itself - (I normally take a 6V bicycle light bulb). \\ 
 + 
 +==== Multi Cell batteries ==== 
 + 
 +Cells in Series → voltages add, capacity stays the same. \\ 
 +Cells in Parallel → capacity adds, voltage stays the same. \\ 
 + 
 +^ Connection     ^ Balancing needed         ^ BMS Needed?           ^ Best use case                        ^ Pros                                         ^ Cons                                         ^ 
 +| Series (S)     | Yes                       | Yes                   | Devices needing higher voltage       | Higher voltage, simpler wiring for high-voltage devices | Needs balancing, single weak cell limits pack, higher safety risk | 
 +| Parallel (P)   | Usually no (should be similar voltage)   | Optional             | Devices needing longer runtime / high current | Higher capacity, lower internal resistance, self-balancing | Voltage of single cell, more complex wiring for many cells | 
 +| Series+Parallel (S×P) | Yes, for series groups     | Yes (for series groups) | High voltage & high capacity devices | Combines high voltage and high capacity | Requires BMS for series groups, more complex wiring | 
 + 
 + 
 +'Balancing' means that the battery cells need to have the same voltage. \\ 
 +Be aware that multi-cells need to be supported and configured properly with the BMS and charger! \\ 
  
 ==== Li-Ion/Li-Po charger modules ==== ==== Li-Ion/Li-Po charger modules ====
Line 139: Line 165:
 *Beware that only IP5306-I2C has I²C-bus (there is a plain IP5306 version too)! You can repurpose CD42 boards though. There is a [[https://github.com/AvinasheeTech/IP5306_I2C|repo with a lib for IP5306-I2C]] \\ *Beware that only IP5306-I2C has I²C-bus (there is a plain IP5306 version too)! You can repurpose CD42 boards though. There is a [[https://github.com/AvinasheeTech/IP5306_I2C|repo with a lib for IP5306-I2C]] \\
  
-IMO: For advanced products, see BQ-series of Texas Instruments: they have everything the heart desires. \\+IMO: For advanced products or custom PCB, see BQ-series of Texas Instruments: they have everything the heart desires. \\ 
 + 
 +For bi-directional boards, to use multiple cells for a power bank, see [[:projects:drill-powerbank-pd#diy_power_bank_pcb_options|DIY power bank PCBs]]. \\
  
 ===== Lithium-titanate batteries ===== ===== Lithium-titanate batteries =====
life_hacks/battery_tips.1760405438.txt.gz · Last modified: by admin
Donate Powered by PHP Valid HTML5 Valid CSS Driven by DokuWiki