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opinion:frater_secessus:self-heated_lifepo4

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opinion:frater_secessus:self-heated_lifepo4 [2025/06/24 18:48]
frater_secessus [charging cutoff]
opinion:frater_secessus:self-heated_lifepo4 [2025/06/24 18:52] (current)
frater_secessus [backing into a minimum temperature setpoint]
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-=== backing into a minimum temperature setpoint ===+==== backing into a minimum temperature setpoint ====
  
-There are a couple steps here:  reading your cell data sheet, and assessing your maximum charging current ([[electrical:12v:battery_capacity|C]]) rate.+There are two pieces of information needed here:  a datasheet for your cells, and a realistic assessment of your maximum charging current ([[electrical:12v:battery_capacity|C rate]]) under best possible conditions.
  
-== what the datasheet tells us ==+=== what the datasheet tells us ===
  
 The cells inside [[electrical:12v:drop-in_lifepo4|your LFP]] are made of individual cells.  These cells are usually made by a big cell manufacturer, who publish datasheets related to those cells.  You may have to google to find out the actual cells inside your battery, or watch a teardown video.  Then you can google to find the datasheet for those cells.   The cells inside [[electrical:12v:drop-in_lifepo4|your LFP]] are made of individual cells.  These cells are usually made by a big cell manufacturer, who publish datasheets related to those cells.  You may have to google to find out the actual cells inside your battery, or watch a teardown video.  Then you can google to find the datasheet for those cells.  
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 | 10°C  T <15°C | 0.2C      | 10°C  T <15°C | 0.2C     
 | 15°C  T <45°C | 0.5C      | 15°C  T <45°C | 0.5C     
- 45°C  T <55°C | 0.2C  |   +| 45°C  T <55°C | 0.2C  |   
 | >55°C | No charging allowed      | >55°C | No charging allowed     
  
  
-== C rate at full charging power ==+=== C rate at full charging power ===
  
-In secessus' use case his charging can  max out at ~55A((and usually much lower)).  55A/280Ah = ~**0.2C**.+In secessus' use case his charging can  max out at ~55A((and usually much lower)) with solar and alternator combined.  55A/280Ah = ~**0.2C**.
  
-== putting it all together ==+=== putting it all together ===
  
-Because his charge rate can reach **0.2C** he chose a warming setpoing of **10°C (50°F)**.+Because his charge rate can reach **0.2C** he chose a warming setpoint of **10°C (50°F)**.
  
  
opinion/frater_secessus/self-heated_lifepo4.1750790898.txt.gz · Last modified: 2025/06/24 18:48 by frater_secessus