From 15fd774062d8688f10a2d3e62afd0b70ff578e17 Mon Sep 17 00:00:00 2001
From: andig <andi@evcc.io>
Date: Sat, 7 Feb 2026 13:14:28 +0100
Subject: [PATCH] Batteries: consolidate measurements api (BC) (#24887)

---
 .../Battery/BatterySettingsModal.vue          |  19 ++--
 .../js/components/Energyflow/Energyflow.vue   |  26 +++--
 .../components/Energyflow/Visualization.vue   |   2 +-
 assets/js/components/Site/Site.vue            |  11 +-
 assets/js/components/Top/Navigation.vue       |   6 +-
 assets/js/types/evcc.ts                       |   9 +-
 assets/js/views/App.vue                       |   2 +-
 core/keys/site.go                             |   8 +-
 core/site.go                                  | 106 +++++++-----------
 core/site_optimizer.go                        |   5 +-
 core/site_tariffs.go                          |   2 +-
 core/site_test.go                             |   9 +-
 core/types/types.go                           |  32 ++++++
 server/helper.go                              |  26 ++++-
 server/influxdb.go                            |  10 +-
 server/influxdb_test.go                       |  22 +++-
 server/mqtt.go                                |  13 ++-
 server/mqtt_test.go                           |  48 +++++---
 18 files changed, 224 insertions(+), 132 deletions(-)
 create mode 100644 core/types/types.go

diff --git a/assets/js/components/Battery/BatterySettingsModal.vue b/assets/js/components/Battery/BatterySettingsModal.vue
index d5ca23cfb..181110c52 100644
--- a/assets/js/components/Battery/BatterySettingsModal.vue
+++ b/assets/js/components/Battery/BatterySettingsModal.vue
@@ -266,7 +266,7 @@ import collector from "@/mixins/collector.js";
 import api from "@/api";
 import settings from "@/settings";
 import { defineComponent, type PropType } from "vue";
-import type { BatteryMeter, SelectOption, CURRENCY, Forecast } from "@/types/evcc";
+import type { Battery, SelectOption, CURRENCY, Forecast } from "@/types/evcc";
 import { SMART_COST_TYPE } from "@/types/evcc";
 
 export default defineComponent({
@@ -276,10 +276,9 @@ export default defineComponent({
 	props: {
 		bufferSoc: { type: Number, default: 100 },
 		prioritySoc: { type: Number, default: 0 },
-		batterySoc: { type: Number, default: 0 },
 		bufferStartSoc: { type: Number, default: 0 },
 		batteryDischargeControl: Boolean,
-		battery: { type: Array as PropType<BatteryMeter[]>, default: () => [] },
+		battery: { type: Object as PropType<Battery> },
 		batteryGridChargeLimit: { type: Number, default: null },
 		smartCostAvailable: Boolean,
 		smartCostType: String as PropType<SMART_COST_TYPE>,
@@ -300,6 +299,12 @@ export default defineComponent({
 		usageTabActive() {
 			return !this.gridTabActive;
 		},
+		batterySoc() {
+			return this.battery?.soc ?? 0;
+		},
+		batteryDevices() {
+			return this.battery?.devices ?? [];
+		},
 		priorityOptions() {
 			const options = [];
 			for (let i = 100; i >= 0; i -= 5) {
@@ -312,7 +317,7 @@ export default defineComponent({
 			return options;
 		},
 		controllable() {
-			return this.battery.some(({ controllable }) => controllable);
+			return this.batteryDevices.some(({ controllable }) => controllable);
 		},
 		gridChargePossible() {
 			return this.controllable && this.isModalVisible && this.smartCostAvailable;
@@ -368,13 +373,13 @@ export default defineComponent({
 			return this.prioritySoc;
 		},
 		batteryDetails() {
-			if (!Array.isArray(this.battery)) {
+			if (!this.batteryDevices.length) {
 				return;
 			}
-			return this.battery
+			const multipleBatteries = this.batteryDevices.length > 1;
+			return this.batteryDevices
 				.filter(({ capacity }) => capacity > 0)
 				.map(({ soc = 0, capacity }) => {
-					const multipleBatteries = this.battery.length > 1;
 					const energy = this.fmtWh(
 						(capacity / 100) * soc * 1e3,
 						POWER_UNIT.KW,
diff --git a/assets/js/components/Energyflow/Energyflow.vue b/assets/js/components/Energyflow/Energyflow.vue
index d28c4a430..09cb851af 100644
--- a/assets/js/components/Energyflow/Energyflow.vue
+++ b/assets/js/components/Energyflow/Energyflow.vue
@@ -129,9 +129,9 @@
 								<template v-if="batteryGridChargeLimitSet" #subline>
 									<div class="d-none d-md-block">&nbsp;</div>
 								</template>
-								<template v-if="battery.length > 1" #expanded>
+								<template v-if="hasMultipleBatteries" #expanded>
 									<EnergyflowEntry
-										v-for="(b, index) in battery"
+										v-for="(b, index) in batteryDevices"
 										:key="index"
 										:name="b.title || genericBatteryTitle(index)"
 										:details="b.soc"
@@ -271,9 +271,9 @@
 										</span>
 									</button>
 								</template>
-								<template v-if="battery.length > 1" #expanded>
+								<template v-if="hasMultipleBatteries" #expanded>
 									<EnergyflowEntry
-										v-for="(b, index) in battery"
+										v-for="(b, index) in batteryDevices"
 										:key="index"
 										:name="b.title || genericBatteryTitle(index)"
 										:details="b.soc"
@@ -316,7 +316,7 @@ import collector from "@/mixins/collector.js";
 import { defineComponent, type PropType } from "vue";
 import {
 	SMART_COST_TYPE,
-	type BatteryMeter,
+	type Battery,
 	type Meter,
 	type CURRENCY,
 	type Forecast,
@@ -342,9 +342,7 @@ export default defineComponent({
 		pvPower: { type: Number, default: 0 },
 		loadpoints: { type: Array as PropType<UiLoadpoint[]>, default: () => [] },
 		batteryConfigured: { type: Boolean },
-		battery: { type: Array as PropType<BatteryMeter[]>, default: () => [] },
-		batteryPower: { type: Number, default: 0 },
-		batterySoc: { type: Number, default: 0 },
+		battery: { type: Object as PropType<Battery> },
 		batteryDischargeControl: { type: Boolean },
 		batteryGridChargeLimit: { type: Number },
 		batteryGridChargeActive: { type: Boolean },
@@ -388,6 +386,18 @@ export default defineComponent({
 		pvProduction() {
 			return Math.abs(this.pvPower);
 		},
+		batterySoc() {
+			return this.battery?.soc;
+		},
+		batteryPower() {
+			return this.battery?.power ?? 0;
+		},
+		batteryDevices() {
+			return this.battery?.devices ?? [];
+		},
+		hasMultipleBatteries() {
+			return this.batteryDevices.length > 1;
+		},
 		batteryDischarge() {
 			return this.dischargePower(this.batteryPower);
 		},
diff --git a/assets/js/components/Energyflow/Visualization.vue b/assets/js/components/Energyflow/Visualization.vue
index 74f05a46b..dfb51978d 100644
--- a/assets/js/components/Energyflow/Visualization.vue
+++ b/assets/js/components/Energyflow/Visualization.vue
@@ -128,13 +128,13 @@ export default defineComponent({
 		selfBattery: { type: Number, default: 0 },
 		pvExport: { type: Number, default: 0 },
 		loadpoints: { type: Array as PropType<UiLoadpoint[]>, default: () => [] },
+		batterySoc: { type: Number },
 		batteryCharge: { type: Number, default: 0 },
 		batteryDischarge: { type: Number, default: 0 },
 		batteryHold: { type: Boolean, default: false },
 		batteryGridCharge: { type: Boolean, default: false },
 		pvProduction: { type: Number, default: 0 },
 		homePower: { type: Number, default: 0 },
-		batterySoc: { type: Number, default: 0 },
 		powerUnit: { type: String as PropType<POWER_UNIT>, default: POWER_UNIT.KW },
 		inPower: { type: Number, default: 0 },
 		outPower: { type: Number, default: 0 },
diff --git a/assets/js/components/Site/Site.vue b/assets/js/components/Site/Site.vue
index 871e26e60..4ca7070ac 100644
--- a/assets/js/components/Site/Site.vue
+++ b/assets/js/components/Site/Site.vue
@@ -88,7 +88,7 @@ import WelcomeIcons from "./WelcomeIcons.vue";
 import { defineComponent, type PropType } from "vue";
 import type {
 	AuthProviders,
-	BatteryMeter,
+	Battery,
 	Meter,
 	CURRENCY,
 	Forecast,
@@ -128,13 +128,11 @@ export default defineComponent({
 		pv: { type: Array as PropType<Meter[]>, default: () => [] },
 		aux: { type: Array as PropType<Meter[]>, default: () => [] },
 		ext: { type: Array as PropType<Meter[]>, default: () => [] },
-		batteryPower: Number,
-		batterySoc: Number,
 		batteryDischargeControl: Boolean,
 		batteryGridChargeLimit: { type: Number, default: null },
 		batteryGridChargeActive: Boolean,
 		batteryMode: String,
-		battery: { type: Array as PropType<BatteryMeter[]>, default: () => [] },
+		battery: { type: Object as PropType<Battery> },
 		gridCurrents: Array,
 		prioritySoc: Number,
 		bufferSoc: Number,
@@ -174,8 +172,11 @@ export default defineComponent({
 		orderedVisibleLoadpoints() {
 			return this.loadpoints.filter((lp) => lp.visible);
 		},
+		batterySoc() {
+			return this.battery?.soc;
+		},
 		batteryConfigured() {
-			return this.battery?.length > 0;
+			return this.battery && this.battery.devices.length > 0;
 		},
 		pvConfigured() {
 			return this.pv?.length > 0;
diff --git a/assets/js/components/Top/Navigation.vue b/assets/js/components/Top/Navigation.vue
index 914068e13..4d96f23db 100644
--- a/assets/js/components/Top/Navigation.vue
+++ b/assets/js/components/Top/Navigation.vue
@@ -154,7 +154,7 @@ import { logout, isLoggedIn, openLoginModal } from "../Auth/auth";
 import { isApp, sendToApp } from "@/utils/native";
 import { isUserConfigError } from "@/utils/fatal";
 import { defineComponent, type PropType } from "vue";
-import type { FatalError, Sponsor, EvOpt, AuthProviders } from "@/types/evcc";
+import type { FatalError, Sponsor, EvOpt, AuthProviders, Battery } from "@/types/evcc";
 
 export default defineComponent({
 	name: "TopNavigation",
@@ -163,7 +163,7 @@ export default defineComponent({
 		authProviders: { type: Object as PropType<AuthProviders>, default: () => ({}) },
 		sponsor: { type: Object as PropType<Sponsor>, default: () => ({}) },
 		forecast: Object,
-		battery: Array,
+		battery: { type: Object as PropType<Battery> },
 		evopt: { type: Object as PropType<EvOpt>, required: false },
 		fatal: { type: Array as PropType<FatalError[]>, default: () => [] },
 	},
@@ -176,7 +176,7 @@ export default defineComponent({
 	},
 	computed: {
 		batteryConfigured() {
-			return this.battery?.length;
+			return this.battery && this.battery.devices.length;
 		},
 		providers() {
 			return Object.entries(this.authProviders)
diff --git a/assets/js/types/evcc.ts b/assets/js/types/evcc.ts
index 4c837df22..6175b9995 100644
--- a/assets/js/types/evcc.ts
+++ b/assets/js/types/evcc.ts
@@ -71,7 +71,7 @@ export interface State {
   version?: string;
   system?: string;
   timezone?: string;
-  battery?: BatteryMeter[];
+  battery?: Battery;
   pv?: Meter[];
   aux?: Meter[];
   ext?: Meter[];
@@ -490,6 +490,13 @@ export interface Meter {
   energy?: number;
 }
 
+export interface Battery {
+  power: number;
+  capacity: number;
+  soc: number;
+  devices: BatteryMeter[];
+}
+
 export interface BatteryMeter extends Meter {
   soc: number;
   controllable: boolean;
diff --git a/assets/js/views/App.vue b/assets/js/views/App.vue
index fc124a33d..0d6931fad 100644
--- a/assets/js/views/App.vue
+++ b/assets/js/views/App.vue
@@ -69,7 +69,7 @@ export default defineComponent({
 			return store.state.version;
 		},
 		batteryModalAvailabe() {
-			return store.state.battery?.length;
+			return store.state.battery?.devices.length;
 		},
 		showRoutes() {
 			return this.state.startupCompleted;
diff --git a/core/keys/site.go b/core/keys/site.go
index 45593e4d0..347693b43 100644
--- a/core/keys/site.go
+++ b/core/keys/site.go
@@ -40,7 +40,6 @@ const (
 	AuxMeters     = "auxMeters"
 
 	// battery settings
-	BatteryCapacity         = "batteryCapacity"
 	BatteryDischargeControl = "batteryDischargeControl"
 	BatteryGridChargeLimit  = "batteryGridChargeLimit"
 	BatteryGridChargeActive = "batteryGridChargeActive"
@@ -48,11 +47,8 @@ const (
 	BufferStartSoc          = "bufferStartSoc"
 
 	// battery status
-	Battery       = "battery"
-	BatteryEnergy = "batteryEnergy"
-	BatteryMode   = "batteryMode"
-	BatteryPower  = "batteryPower"
-	BatterySoc    = "batterySoc"
+	Battery     = "battery"
+	BatteryMode = "batteryMode"
 
 	// external battery control
 	BatteryModeExternal = "batteryModeExternal"
diff --git a/core/site.go b/core/site.go
index de542f2be..3db503fb3 100644
--- a/core/site.go
+++ b/core/site.go
@@ -25,6 +25,7 @@ import (
 	"github.com/evcc-io/evcc/core/session"
 	"github.com/evcc-io/evcc/core/site"
 	"github.com/evcc-io/evcc/core/soc"
+	"github.com/evcc-io/evcc/core/types"
 	"github.com/evcc-io/evcc/core/vehicle"
 	"github.com/evcc-io/evcc/push"
 	"github.com/evcc-io/evcc/server/db"
@@ -48,27 +49,6 @@ type updater interface {
 	Update(sitePower, batteryBoostPower float64, consumption, feedin api.Rates, batteryBuffered, batteryStart bool, greenShare float64, effectivePrice, effectiveCo2 *float64)
 }
 
-// measurement is used as slice element for publishing structured data
-type measurement struct {
-	Title         string    `json:"title,omitempty"`
-	Icon          string    `json:"icon,omitempty"`
-	Power         float64   `json:"power"`
-	Energy        float64   `json:"energy,omitempty"`
-	Powers        []float64 `json:"powers,omitempty"`
-	Currents      []float64 `json:"currents,omitempty"`
-	ExcessDCPower float64   `json:"excessdcpower,omitempty"`
-	Capacity      *float64  `json:"capacity,omitempty"`
-	Soc           *float64  `json:"soc,omitempty"`
-	Controllable  *bool     `json:"controllable,omitempty"`
-}
-
-var _ api.TitleDescriber = (*measurement)(nil)
-
-// GetTitle implements api.TitleDescriber interface for InfluxDB tagging
-func (m measurement) GetTitle() string {
-	return m.Title
-}
-
 var _ site.API = (*Site)(nil)
 
 // Site is the main configuration container. A site can host multiple loadpoints.
@@ -112,16 +92,14 @@ type Site struct {
 	householdSlotStart time.Time
 
 	// cached state
-	gridPower                float64         // Grid power
-	pvPower                  float64         // PV power
-	excessDCPower            float64         // PV excess DC charge power (hybrid only)
-	auxPower                 float64         // Aux power
-	batteryPower             float64         // Battery power (charge negative, discharge positive)
-	batterySoc               float64         // Battery soc
-	batteryCapacity          float64         // Battery capacity
-	batteryMode              api.BatteryMode // Battery mode (runtime only, not persisted)
-	batteryModeExternal      api.BatteryMode // Battery mode (external, runtime only, not persisted)
-	batteryModeExternalTimer time.Time       // Battery mode timer for external control
+	gridPower                float64            // Grid power
+	pvPower                  float64            // PV power
+	excessDCPower            float64            // PV excess DC charge power (hybrid only)
+	auxPower                 float64            // Aux power
+	battery                  types.BatteryState // Battery cached and published state
+	batteryMode              api.BatteryMode    // Battery mode (runtime only, not persisted)
+	batteryModeExternal      api.BatteryMode    // Battery mode (external, runtime only, not persisted)
+	batteryModeExternalTimer time.Time          // Battery mode timer for external control
 }
 
 // MetersConfig contains the site's meter configuration
@@ -501,8 +479,8 @@ func (site *Site) clearPlanLocks() {
 	}
 }
 
-func (site *Site) collectMeters(key string, meters []config.Device[api.Meter]) []measurement {
-	mm := make([]measurement, len(meters))
+func (site *Site) collectMeters(key string, meters []config.Device[api.Meter]) []types.Measurement {
+	mm := make([]types.Measurement, len(meters))
 
 	fun := func(i int, dev config.Device[api.Meter]) {
 		meter := dev.Instance()
@@ -529,7 +507,7 @@ func (site *Site) collectMeters(key string, meters []config.Device[api.Meter]) [
 		}
 
 		props := deviceProperties(dev)
-		mm[i] = measurement{
+		mm[i] = types.Measurement{
 			Title:  props.Title,
 			Icon:   props.Icon,
 			Power:  power,
@@ -573,13 +551,13 @@ func (site *Site) updatePvMeters() {
 		}
 	}
 
-	site.pvPower = lo.SumBy(mm, func(m measurement) float64 {
+	site.pvPower = lo.SumBy(mm, func(m types.Measurement) float64 {
 		return max(0, m.Power)
 	})
-	site.excessDCPower = lo.SumBy(mm, func(m measurement) float64 {
+	site.excessDCPower = lo.SumBy(mm, func(m types.Measurement) float64 {
 		return math.Abs(m.ExcessDCPower)
 	})
-	totalEnergy := lo.SumBy(mm, func(m measurement) float64 {
+	totalEnergy := lo.SumBy(mm, func(m types.Measurement) float64 {
 		return m.Energy
 	})
 
@@ -622,7 +600,7 @@ func (site *Site) updatePvMeters() {
 }
 
 // updateBatteryMeters updates battery meters
-func (site *Site) updateBatteryMeters() []measurement {
+func (site *Site) updateBatteryMeters() []types.Measurement {
 	if len(site.batteryMeters) == 0 {
 		return nil
 	}
@@ -652,7 +630,7 @@ func (site *Site) updateBatteryMeters() []measurement {
 		mm[i].Controllable = lo.ToPtr(controllable)
 	}
 
-	batterySocAcc := lo.SumBy(mm, func(m measurement) float64 {
+	batterySocAcc := lo.SumBy(mm, func(m types.Measurement) float64 {
 		if m.Soc == nil {
 			return 0
 		}
@@ -662,7 +640,7 @@ func (site *Site) updateBatteryMeters() []measurement {
 		}
 		return *m.Soc
 	})
-	totalCapacity := lo.SumBy(mm, func(m measurement) float64 {
+	totalCapacity := lo.SumBy(mm, func(m types.Measurement) float64 {
 		if m.Capacity == nil {
 			return 0
 		}
@@ -673,27 +651,23 @@ func (site *Site) updateBatteryMeters() []measurement {
 	if totalCapacity == 0 {
 		totalCapacity = float64(len(site.batteryMeters))
 	}
-	site.batterySoc = batterySocAcc / totalCapacity
-	site.batteryCapacity = totalCapacity
+	site.battery.Soc = batterySocAcc / totalCapacity
+	site.battery.Capacity = totalCapacity
 
-	site.batteryPower = lo.SumBy(mm, func(m measurement) float64 {
+	site.battery.Power = lo.SumBy(mm, func(m types.Measurement) float64 {
 		return m.Power
 	})
-	totalEnergy := lo.SumBy(mm, func(m measurement) float64 {
+	site.battery.Energy = lo.SumBy(mm, func(m types.Measurement) float64 {
 		return m.Energy
 	})
 
 	if len(site.batteryMeters) > 1 {
-		site.log.DEBUG.Printf("battery power: %.0fW", site.batteryPower)
-		site.log.DEBUG.Printf("battery soc: %.0f%%", math.Round(site.batterySoc))
+		site.log.DEBUG.Printf("battery power: %.0fW", site.battery.Power)
+		site.log.DEBUG.Printf("battery soc: %.0f%%", math.Round(site.battery.Soc))
 	}
 
-	site.publish(keys.BatteryCapacity, site.batteryCapacity)
-	site.publish(keys.BatterySoc, site.batterySoc)
-
-	site.publish(keys.BatteryPower, site.batteryPower)
-	site.publish(keys.BatteryEnergy, totalEnergy)
-	site.publish(keys.Battery, mm)
+	site.battery.Devices = mm
+	site.publish(keys.Battery, site.battery)
 
 	return mm
 }
@@ -705,7 +679,7 @@ func (site *Site) updateAuxMeters() {
 	}
 
 	mm := site.collectMeters("aux", site.auxMeters)
-	site.auxPower = lo.SumBy(mm, func(m measurement) float64 {
+	site.auxPower = lo.SumBy(mm, func(m types.Measurement) float64 {
 		return m.Power
 	})
 
@@ -733,7 +707,7 @@ func (site *Site) updateGridMeter() error {
 		return nil
 	}
 
-	var mm measurement
+	var mm types.Measurement
 
 	if res, err := backoff.RetryWithData(site.gridMeter.CurrentPower, modbus.Backoff()); err == nil {
 		mm.Power = res
@@ -782,7 +756,7 @@ func (site *Site) updateGridMeter() error {
 func (site *Site) updateMeters() error {
 	var eg errgroup.Group
 
-	var battery []measurement
+	var battery []types.Measurement
 
 	eg.Go(func() error { site.updatePvMeters(); return nil })
 	eg.Go(func() error { battery = site.updateBatteryMeters(); return nil })
@@ -841,12 +815,12 @@ func (site *Site) sitePower(totalChargePower, flexiblePower float64) (float64, b
 	// allow using PV as estimate for grid power
 	if site.gridMeter == nil {
 		site.gridPower = totalChargePower - site.pvPower
-		site.publish(keys.Grid, measurement{Power: site.gridPower})
+		site.publish(keys.Grid, types.Measurement{Power: site.gridPower})
 	}
 
 	// ensure safe default for residual power
 	residualPower := site.GetResidualPower()
-	if len(site.batteryMeters) > 0 && site.batterySoc < site.prioritySoc && residualPower <= 0 {
+	if len(site.batteryMeters) > 0 && site.battery.Soc < site.prioritySoc && residualPower <= 0 {
 		residualPower = 100 // Wsite.publish(keys.PvPower,
 	}
 
@@ -861,7 +835,7 @@ func (site *Site) sitePower(totalChargePower, flexiblePower float64) (float64, b
 	}
 
 	// honour battery priority
-	batteryPower := site.batteryPower
+	batteryPower := site.battery.Power
 	excessDCPower := site.excessDCPower
 
 	// handed to loadpoint
@@ -872,14 +846,14 @@ func (site *Site) sitePower(totalChargePower, flexiblePower float64) (float64, b
 		defer site.RUnlock()
 
 		// if battery is charging below prioritySoc give it priority
-		if site.batterySoc < site.prioritySoc && batteryPower < 0 {
-			site.log.DEBUG.Printf("battery has priority at soc %.0f%% (< %.0f%%)", site.batterySoc, site.prioritySoc)
+		if site.battery.Soc < site.prioritySoc && batteryPower < 0 {
+			site.log.DEBUG.Printf("battery has priority at soc %.0f%% (< %.0f%%)", site.battery.Soc, site.prioritySoc)
 			batteryPower = 0
 			excessDCPower = 0
 		} else {
 			// if battery is above bufferSoc allow using it for charging
-			batteryBuffered = site.bufferSoc > 0 && site.batterySoc > site.bufferSoc
-			batteryStart = site.bufferStartSoc > 0 && site.batterySoc > site.bufferStartSoc
+			batteryBuffered = site.bufferSoc > 0 && site.battery.Soc > site.bufferSoc
+			batteryStart = site.bufferStartSoc > 0 && site.battery.Soc > site.bufferStartSoc
 		}
 	}
 
@@ -969,7 +943,7 @@ func (site *Site) update(lp updater) {
 
 	if sitePower, batteryBuffered, batteryStart, err := site.sitePower(totalChargePower, flexiblePower); err == nil {
 		// ignore negative pvPower values as that means it is not an energy source but consumption
-		homePower := site.gridPower + max(0, site.pvPower) + site.batteryPower - totalChargePower
+		homePower := site.gridPower + max(0, site.pvPower) + site.battery.Power - totalChargePower
 		homePower = max(homePower, 0)
 		site.publish(keys.HomePower, homePower)
 
@@ -979,14 +953,14 @@ func (site *Site) update(lp updater) {
 
 		// add battery charging power to homePower to ignore all consumption which does not occur on loadpoints
 		// fix for: https://github.com/evcc-io/evcc/issues/11032
-		nonChargePower := homePower + max(0, -site.batteryPower)
+		nonChargePower := homePower + max(0, -site.battery.Power)
 		greenShareHome := site.greenShare(0, homePower)
 		greenShareLoadpoints := site.greenShare(nonChargePower, nonChargePower+totalChargePower)
 
 		// TODO
 		if lp != nil {
 			lp.Update(
-				sitePower, max(0, site.batteryPower), consumption, feedin, batteryBuffered, batteryStart,
+				sitePower, max(0, site.battery.Power), consumption, feedin, batteryBuffered, batteryStart,
 				greenShareLoadpoints, site.effectivePrice(greenShareLoadpoints), site.effectiveCo2(greenShareLoadpoints),
 			)
 		}
@@ -1033,9 +1007,9 @@ func (site *Site) prepare() {
 	site.publish(keys.GridConfigured, site.gridMeter != nil)
 	site.publish(keys.Grid, api.Meter(nil))
 	site.publish(keys.Pv, []api.Meter{})
-	site.publish(keys.Battery, []api.Meter{})
 	site.publish(keys.Aux, []api.Meter{})
 	site.publish(keys.Ext, []api.Meter{})
+	site.publish(keys.Battery, nil)
 	site.publish(keys.PrioritySoc, site.prioritySoc)
 	site.publish(keys.BufferSoc, site.bufferSoc)
 	site.publish(keys.BufferStartSoc, site.bufferStartSoc)
diff --git a/core/site_optimizer.go b/core/site_optimizer.go
index 9fc048937..6b04f891c 100644
--- a/core/site_optimizer.go
+++ b/core/site_optimizer.go
@@ -15,6 +15,7 @@ import (
 	"github.com/evcc-io/evcc/api"
 	"github.com/evcc-io/evcc/core/loadpoint"
 	"github.com/evcc-io/evcc/core/metrics"
+	"github.com/evcc-io/evcc/core/types"
 	"github.com/evcc-io/evcc/tariff"
 	"github.com/evcc-io/evcc/util/config"
 	"github.com/evcc-io/evcc/util/request"
@@ -54,7 +55,7 @@ type responseDetails struct {
 
 const slotsPerHour = float64(time.Hour / tariff.SlotDuration)
 
-func (site *Site) optimizerUpdateAsync(battery []measurement) {
+func (site *Site) optimizerUpdateAsync(battery []types.Measurement) {
 	var err error
 
 	if time.Since(updated) < 2*time.Minute {
@@ -81,7 +82,7 @@ func (site *Site) optimizerUpdateAsync(battery []measurement) {
 	err = site.optimizerUpdate(battery)
 }
 
-func (site *Site) optimizerUpdate(battery []measurement) error {
+func (site *Site) optimizerUpdate(battery []types.Measurement) error {
 	uri := os.Getenv("EVOPT_URI")
 	if uri == "" {
 		return nil
diff --git a/core/site_tariffs.go b/core/site_tariffs.go
index 0bd2d247b..916b22934 100644
--- a/core/site_tariffs.go
+++ b/core/site_tariffs.go
@@ -32,7 +32,7 @@ type dailyDetails struct {
 //   - the current green share, calculated for the part of the consumption between powerFrom and powerTo
 //     the consumption below powerFrom will get the available green power first
 func (site *Site) greenShare(powerFrom float64, powerTo float64) float64 {
-	greenPower := math.Max(0, site.pvPower) + math.Max(0, site.batteryPower)
+	greenPower := math.Max(0, site.pvPower) + math.Max(0, site.battery.Power)
 	greenPowerAvailable := math.Max(0, greenPower-powerFrom)
 
 	power := powerTo - powerFrom
diff --git a/core/site_test.go b/core/site_test.go
index 7885c978b..e12b1233f 100644
--- a/core/site_test.go
+++ b/core/site_test.go
@@ -6,6 +6,7 @@ import (
 
 	"github.com/benbjohnson/clock"
 	"github.com/evcc-io/evcc/api"
+	"github.com/evcc-io/evcc/core/types"
 	"github.com/evcc-io/evcc/server/db"
 	"github.com/evcc-io/evcc/util"
 	"github.com/evcc-io/evcc/util/config"
@@ -105,9 +106,11 @@ func TestGreenShare(t *testing.T) {
 		t.Log(tc.title)
 
 		s := &Site{
-			gridPower:    tc.grid,
-			pvPower:      tc.pv,
-			batteryPower: tc.battery,
+			gridPower: tc.grid,
+			pvPower:   tc.pv,
+			battery: types.BatteryState{
+				Power: tc.battery,
+			},
 		}
 
 		totalPower := tc.grid + tc.pv + max(0, tc.battery)
diff --git a/core/types/types.go b/core/types/types.go
new file mode 100644
index 000000000..3a167b06c
--- /dev/null
+++ b/core/types/types.go
@@ -0,0 +1,32 @@
+package types
+
+import "github.com/evcc-io/evcc/api"
+
+// Measurement is the device measurements struct
+type Measurement struct {
+	Title         string    `json:"title,omitempty"`
+	Icon          string    `json:"icon,omitempty"`
+	Power         float64   `json:"power"`
+	Energy        float64   `json:"energy,omitempty"`
+	Powers        []float64 `json:"powers,omitempty"`
+	Currents      []float64 `json:"currents,omitempty"`
+	ExcessDCPower float64   `json:"excessdcpower,omitempty"`
+	Capacity      *float64  `json:"capacity,omitempty"`
+	Soc           *float64  `json:"soc,omitempty"`
+	Controllable  *bool     `json:"controllable,omitempty"`
+}
+
+var _ api.TitleDescriber = (*Measurement)(nil)
+
+// GetTitle implements api.TitleDescriber interface for InfluxDB tagging
+func (m Measurement) GetTitle() string {
+	return m.Title
+}
+
+type BatteryState struct {
+	Power    float64       `json:"power"`
+	Energy   float64       `json:"energy,omitempty"`
+	Capacity float64       `json:"capacity,omitempty"`
+	Soc      float64       `json:"soc"`
+	Devices  []Measurement `json:"devices,omitempty" influxdb:"battery"`
+}
diff --git a/server/helper.go b/server/helper.go
index ed6c84428..f63fc455b 100644
--- a/server/helper.go
+++ b/server/helper.go
@@ -35,9 +35,25 @@ func jsonDecoder(r io.Reader) *json.Decoder {
 	return dec
 }
 
-// omitEmpty returns true if struct field is omitempty
-func omitEmpty(f reflect.StructField) bool {
-	tag := f.Tag.Get("json")
-	values := strings.Split(tag, ",")
-	return slices.Contains(values, "omitempty")
+// jsonOmitEmpty returns true if struct field is omitempty
+func jsonOmitEmpty(f reflect.StructField) bool {
+	return tagAttribute("json", "omitempty", f)
+}
+
+// tagValue returns the given tag's primary value
+func tagValue(key string, f reflect.StructField) string {
+	if tag := f.Tag.Get(key); tag != "" {
+		return strings.Split(tag, ",")[0]
+	}
+	return ""
+}
+
+// tagAttribute returns the given tag's primary value
+func tagAttribute(key, attr string, f reflect.StructField) bool {
+	if tag := f.Tag.Get(key); tag != "" {
+		if attrs := strings.Split(tag, ","); len(attrs) > 1 {
+			return slices.Contains(attrs[1:], attr)
+		}
+	}
+	return false
 }
diff --git a/server/influxdb.go b/server/influxdb.go
index 1a35be6b0..264394d85 100644
--- a/server/influxdb.go
+++ b/server/influxdb.go
@@ -62,6 +62,10 @@ type pointWriter interface {
 	WritePoint(point *write.Point)
 }
 
+func influxTagValue(f reflect.StructField) string {
+	return tagValue("influxdb", f)
+}
+
 // writePoint asynchronously writes a point to influx
 func (m *Influx) writePoint(writer pointWriter, key string, fields map[string]any, tags map[string]string) {
 	m.log.TRACE.Printf("write %s=%v (%v)", key, fields, tags)
@@ -79,11 +83,15 @@ func (m *Influx) writeComplexPoint(writer pointWriter, key string, val any, tags
 
 		for i := range typ.NumField() {
 			if f := typ.Field(i); f.IsExported() {
-				if val.Field(i).IsZero() && omitEmpty(f) {
+				if val.Field(i).IsZero() && jsonOmitEmpty(f) {
 					continue
 				}
 
 				key := key + strings.ToUpper(f.Name[:1]) + f.Name[1:]
+				if tag := influxTagValue(f); tag != "" {
+					key = tag
+				}
+
 				val := val.Field(i).Interface()
 
 				m.writeComplexPoint(writer, key, val, tags)
diff --git a/server/influxdb_test.go b/server/influxdb_test.go
index fa55323db..2da388d1b 100644
--- a/server/influxdb_test.go
+++ b/server/influxdb_test.go
@@ -4,6 +4,7 @@ import (
 	"testing"
 
 	"github.com/benbjohnson/clock"
+	"github.com/evcc-io/evcc/core/types"
 	"github.com/evcc-io/evcc/util"
 	inf2 "github.com/influxdata/influxdb-client-go/v2"
 	"github.com/influxdata/influxdb-client-go/v2/api/write"
@@ -88,7 +89,7 @@ func (w *influxSuite) TestSlice() {
 }
 
 func (w *influxSuite) TestMeasurement() {
-	w.WriteParam(util.Param{Key: "battery", Val: measurement{Power: 1, Soc: lo.ToPtr(10.0)}})
+	w.WriteParam(util.Param{Key: "battery", Val: types.Measurement{Power: 1, Soc: lo.ToPtr(10.0)}})
 	w.Equal([]*write.Point{
 		inf2.NewPoint("batteryPower", nil, map[string]any{"value": 1.0}, w.clock.Now()),
 		inf2.NewPoint("batterySoc", nil, map[string]any{"value": 10.0}, w.clock.Now()),
@@ -96,7 +97,7 @@ func (w *influxSuite) TestMeasurement() {
 }
 
 func (w *influxSuite) TestSliceOfStruct() {
-	w.WriteParam(util.Param{Key: "grid", Val: []measurement{
+	w.WriteParam(util.Param{Key: "grid", Val: []types.Measurement{
 		{Power: 1, Soc: lo.ToPtr(10.0)},
 		{Power: 2, Soc: lo.ToPtr(20.0)},
 	}})
@@ -107,3 +108,20 @@ func (w *influxSuite) TestSliceOfStruct() {
 		inf2.NewPoint("gridSoc", map[string]string{"id": "2"}, map[string]any{"value": 20.0}, w.clock.Now()),
 	}, w.p)
 }
+
+func (w *influxSuite) TestBatteryState() {
+	w.WriteParam(util.Param{Key: "battery", Val: types.BatteryState{
+		Power: 2,
+		Soc:   20.0,
+		Devices: []types.Measurement{{
+			Power: 1,
+			Soc:   lo.ToPtr(10.0),
+		}},
+	}})
+	w.Equal([]*write.Point{
+		inf2.NewPoint("batteryPower", map[string]string{}, map[string]any{"value": 2.0}, w.clock.Now()),
+		inf2.NewPoint("batterySoc", map[string]string{}, map[string]any{"value": 20.0}, w.clock.Now()),
+		inf2.NewPoint("batteryPower", map[string]string{"id": "1"}, map[string]any{"value": 1.0}, w.clock.Now()),
+		inf2.NewPoint("batterySoc", map[string]string{"id": "1"}, map[string]any{"value": 10.0}, w.clock.Now()),
+	}, w.p)
+}
diff --git a/server/mqtt.go b/server/mqtt.go
index df08689b4..940b20d92 100644
--- a/server/mqtt.go
+++ b/server/mqtt.go
@@ -79,6 +79,10 @@ func (m *MQTT) encode(v any) string {
 	}
 }
 
+func mqttTagAttribute(attr string, f reflect.StructField) bool {
+	return tagAttribute("mqtt", attr, f)
+}
+
 func (m *MQTT) publishComplex(topic string, retained bool, payload any) {
 	if _, ok := payload.(fmt.Stringer); ok || payload == nil {
 		m.publishSingleValue(topic, retained, payload)
@@ -129,9 +133,14 @@ func (m *MQTT) publishComplex(topic string, retained bool, payload any) {
 		// loop struct
 		for i := range typ.NumField() {
 			if f := typ.Field(i); f.IsExported() {
-				topic := fmt.Sprintf("%s/%s", topic, strings.ToLower(f.Name[:1])+f.Name[1:])
+				topic := topic
+				if !mqttTagAttribute("squash", f) {
+					topic = fmt.Sprintf("%s/%s", topic, strings.ToLower(f.Name[:1])+f.Name[1:])
+				} else {
+					println(1)
+				}
 
-				if val.Field(i).IsZero() && omitEmpty(f) {
+				if val.Field(i).IsZero() && jsonOmitEmpty(f) {
 					m.publishSingleValue(topic, retained, nil)
 				} else {
 					m.publishComplex(topic, retained, val.Field(i).Interface())
diff --git a/server/mqtt_test.go b/server/mqtt_test.go
index 4e1822cbe..ba79be409 100644
--- a/server/mqtt_test.go
+++ b/server/mqtt_test.go
@@ -7,6 +7,7 @@ import (
 	"testing"
 	"time"
 
+	"github.com/evcc-io/evcc/core/types"
 	"github.com/samber/lo"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/suite"
@@ -18,14 +19,6 @@ func TestMqttNaNInf(t *testing.T) {
 	assert.Equal(t, "+Inf", m.encode(math.Inf(0)), "Inf not encoded as string")
 }
 
-type measurement struct {
-	Power        float64   `json:"power"`
-	Energy       float64   `json:"energy,omitempty"`
-	Currents     []float64 `json:"currents,omitempty"`
-	Soc          *float64  `json:"soc,omitempty"`
-	Controllable *bool     `json:"controllable,omitempty"`
-}
-
 func TestMqttTypes(t *testing.T) {
 	suite.Run(t, new(mqttSuite))
 }
@@ -104,22 +97,41 @@ func (suite *mqttSuite) TestSlice() {
 	suite.Equal([]string{"2", "10", "20"}, suite.payloads, "payloads")
 }
 
-func (suite *mqttSuite) TestGrid() {
-	topics := []string{"test/power", "test/energy", "test/currents", "test/soc", "test/controllable"}
+func (suite *mqttSuite) TestMeasurement() {
+	topics := []string{"test/title", "test/icon", "test/power", "test/energy", "test/powers", "test/currents", "test/excessDCPower", "test/capacity", "test/soc", "test/controllable"}
 
-	suite.publish("test", false, measurement{})
+	suite.publish("test", false, types.Measurement{})
 	suite.Equal(topics, suite.topics, "topics")
-	suite.Equal([]string{"0", "", "", "", ""}, suite.payloads, "payloads")
+	suite.Equal([]string{"", "", "0", "", "", "", "", "", "", ""}, suite.payloads, "payloads")
 
-	suite.publish("test", false, measurement{Energy: 1})
+	suite.publish("test", false, types.Measurement{Energy: 1})
 	suite.Equal(topics, suite.topics, "topics")
-	suite.Equal([]string{"0", "1", "", "", ""}, suite.payloads, "payloads")
+	suite.Equal([]string{"", "", "0", "1", "", "", "", "", "", ""}, suite.payloads, "payloads")
 
-	suite.publish("test", false, measurement{Controllable: lo.ToPtr(false)})
+	suite.publish("test", false, types.Measurement{Controllable: lo.ToPtr(false)})
 	suite.Equal(topics, suite.topics, "topics")
-	suite.Equal([]string{"0", "", "", "", "false"}, suite.payloads, "payloads")
+	suite.Equal([]string{"", "", "0", "", "", "", "", "", "", "false"}, suite.payloads, "payloads")
 
-	suite.publish("test", false, measurement{Currents: []float64{1, 2, 3}})
+	suite.publish("test", false, types.Measurement{Currents: []float64{1, 2, 3}})
 	suite.Equal(append(topics, "test/currents/1", "test/currents/2", "test/currents/3"), suite.topics, "topics")
-	suite.Equal([]string{"0", "", "3", "", "", "1", "2", "3"}, suite.payloads, "payloads")
+	suite.Equal([]string{"", "", "0", "", "", "3", "", "", "", "", "1", "2", "3"}, suite.payloads, "payloads")
+}
+
+func (suite *mqttSuite) TestBatteryState() {
+	topics := []string{
+		"test/power", "test/energy", "test/capacity", "test/soc", "test/devices",
+		"test/devices/1/title", "test/devices/1/icon", "test/devices/1/power", "test/devices/1/energy", "test/devices/1/powers", "test/devices/1/currents", "test/devices/1/excessDCPower", "test/devices/1/capacity", "test/devices/1/soc", "test/devices/1/controllable",
+	}
+
+	suite.publish("test", false, types.BatteryState{
+		Power: 2,
+		Soc:   20.0,
+		Devices: []types.Measurement{{
+			Power: 1,
+			Soc:   lo.ToPtr(10.0),
+		}},
+	})
+
+	suite.Equal(topics, suite.topics, "topics")
+	suite.Equal([]string{"2", "", "", "20", "1", "", "", "1", "", "", "", "", "", "10", ""}, suite.payloads, "payloads")
 }