Dell notebook D500 D600 9 pin battery connector.
The Dell Latitude D500/D600 battery (type 3R305, also sold as part C1295) is a 9-pin Smart Battery System (SBS) pack rated at 11.1 V and 4400 mAh containing six Li-Ion cells. It conforms to the Smart Battery Data Specification Rev 1.1 (SBS-IF, December 1998), which mandates SMBus (2-wire serial: SDA + SCL) communication between the battery’s fuel-gauge IC and the host system for state-of-charge, voltage, and temperature reporting. The same pack fits multiple Dell Latitude and Inspiron models of the early 2000s. Like all SBS packs, the physical connector pinout is manufacturer-specific and not defined by the standard itself.
Type: Li-ion, Voltage: 11.1 V, Capacity: 4400mAh, Size: 127.40 x 77.40 x 19.40 mm
Dell 3R305 battery parts number: 451-10132 , U1544 , J2178 , G2053A01 , C1295 , BAT1194 , 9X821 , 4P894 , 451-10194 , W1605 , 310-5195 , 6Y270 , 312-0191 , 310-4482 , 3R305 , 312-0090 , 1X793 , 315-0084 , 312-0068 , 0X217 , 312-0309.
Dell 3R305 battery fit laptop: Inspiron 500m , Inspiron 510m , Inspiron 600m , Latitude D500 , Latitude D505 , Latitude D510 , Latitude D520 , Latitude D600 , Latitude D610 , Precision M20.
| Pin | Name | Description |
|---|---|---|
| 1 | BAT+ | Positive battery terminal |
| 2 | BAT+ | Positive battery terminal |
| 3 | ? | UNKNOW (SCL ?) |
| 4 | SMBD or SDA | SM Bus Data, Serial Data - the positive signal is 3.3V |
| 5 | GND | Ground |
| 6 | ? | UNKNOW |
| 7 | ON/OFF | (the positive signal is 3.3V) |
| 8 | BAT- | Negative battery terminal |
| 9 | BAT- | Negative battery terminal |
Notes
- The battery contains 6 lithium-ion cells (3 sets of 2 cells in parallel).
- Each cell has a 3.7 V max, so the total battery voltage is 3.7 × 3 = 11.1 V.
- The connector is non-latching; the battery’s mechanical seating holds contact pressure.
- Pin numbering orientation (left-to-right vs. right-to-left as viewed from the battery side) is not documented in the Dell Latitude D600 Service Manual; the table above follows the convention used in community measurements. The power pins (BAT+, BAT−) are duplicated to handle the higher current load.
- SMBus clock and data lines carry no internal pull-up resistors on the battery side; pull-ups are provided by the host system.
Signals
- BAT+ — Positive battery power terminal (pins 1 and 2 are electrically joined to share current capacity).
- ? (pin 3, likely SCL) — Probable SMBus Clock line (SCL); purpose not publicly documented in Dell service documentation.
- SMBD or SDA — SMBus Serial Data (SDA); the fuel-gauge IC inside the pack uses this line together with SCL to report voltage, current, capacity, temperature, and state-of-charge to the host over a standard SMBus register set.
- GND — Battery negative / system ground reference.
- ? (pin 6) — Purpose not publicly documented; likely Battery Enable / System Present or Safety Signal (thermistor output).
- ON/OFF — Battery enable or system-present signal; asserted by the host to activate the pack output.
- BAT− — Negative battery power terminal (pins 8 and 9 are electrically joined).
References
- Smart Battery Data Specification Revision 1.1 — SBS Implementers Forum, December 1998; governing standard for SMBus communication, Safety Signal, and battery-side electrical interface.
- System Management Bus (SMBus) Specification 2.0 — SMBus Working Group / SMIF; defines the 2-wire SDA/SCL serial bus used by SBS battery packs.
- Dell Latitude D600 Service Manual — Dell, Inc. (archived on Internet Archive); confirms 11.1 V Li-Ion battery type 3R305/C1295 and compatible models.