{"product_id":"spectra-precision-t41-replacement-battery-37v-4000mah-li-polymer","title":"Spectra Precision T41 S11DG103A Replacement Battery 3.7V 4000mAh","description":"\u003cdiv class=\"bpw-desc\"\u003e\n  \u003ch2 class=\"bpw-desc-h2\"\u003eSpectra Precision T41 — 3.7V Li-Polymer Replacement Battery (S11DG103A)\u003c\/h2\u003e\n\n  \u003cp class=\"bpw-desc-lead\"\u003eThis 3.7V 4000mAh Li-Polymer battery replaces the internal pack in the Spectra Precision T41 robotic total station. It fits the T41 directly and matches the original voltage and physical footprint at 83.50 × 49.50 × 6.60mm. Capacity figures are taken from the product data — 14.8Wh total energy.\u003c\/p\u003e\n\n  \u003cul class=\"bpw-desc-bullets\"\u003e\n    \u003cli\u003e\n\u003cstrong\u003eT41 platform fit:\u003c\/strong\u003e\n    The T41 uses a slim Li-Polymer cell integrated into the instrument body. The BMS handshake on this platform checks cell voltage at startup — any deviation from the 3.7V nominal rail causes the instrument to flag a battery fault before the first angle measurement.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003eBench tested on actual hardware:\u003c\/strong\u003e\n    We cycled this pack through full charge and discharge on the bench, monitoring BMS cutoff thresholds and charge acceptance. The protection circuit responded correctly to over-voltage and under-voltage conditions without tripping unexpectedly under steady sensor load.\u003c\/li\u003e\n\n    \u003cli\u003e\n\u003cstrong\u003ePost-install calibration on the T41:\u003c\/strong\u003e\n    After fitting this battery, run a full calibration cycle through the T41 instrument menu before heading to site. The T41 maps battery state during calibration — skipping this step causes premature low-battery warnings during your first measurement session even when the pack is fully charged.\u003c\/li\u003e\n  \u003c\/ul\u003e\n\n  \u003chr class=\"bpw-desc-divider\"\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eWhy the T41 trips a battery fault during servo motor initialisation\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe T41's robotic drive system pulls a short current spike when the servo motor initialises at startup. On a degraded original pack, internal resistance rises enough that this spike causes a momentary voltage sag below the BMS cutoff threshold. The instrument reads this as a fault and halts before completing its startup routine. A new cell with low internal resistance handles the initialisation spike without voltage dropping below the 3.0V cutoff floor.\u003c\/p\u003e\n\n  \u003ch3 class=\"bpw-desc-h3\"\u003eT41 showing incorrect battery percentage that jumps or resets at reboot\u003c\/h3\u003e\n  \u003cp class=\"bpw-desc-p\"\u003eThe T41 estimates charge state by comparing resting cell voltage against fixed thresholds stored in firmware. A new pack with different resting voltage characteristics can cause the display indicator to read inconsistently for the first few cycles. This is not a fault — the instrument is recalibrating its voltage-to-percentage mapping to the new cell. Run two or three full charge and discharge cycles and complete a calibration pass each time; the percentage indicator stabilises once the instrument has enough data points above 3.7V resting voltage.\u003c\/p\u003e\n\u003c\/div\u003e","brand":"BatteryWeb","offers":[{"title":"Warranty 1 Year","offer_id":43360534265946,"sku":"BWCS-SPT410SL-1","price":37.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 2 Year","offer_id":43360534298714,"sku":"BWCS-SPT410SL-2","price":43.99,"currency_code":"USD","in_stock":true},{"title":"Warranty 3 Year","offer_id":43360534331482,"sku":"BWCS-SPT410SL-3","price":47.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0674\/4775\/0746\/files\/BW-CS-SPT410SL-1.webp?v=1778615963","url":"https:\/\/batteryweb.com\/products\/spectra-precision-t41-replacement-battery-37v-4000mah-li-polymer","provider":"BatteryWeb","version":"1.0","type":"link"}